[
  {
    "index": 14673,
    "id": 25904,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Each angle of the equilateral triangle is 60°.<br>From the fold, ∠b = 180° − 77° − 60° = 43°.<br>Then ∠a = 180° − 43° − 43° = 94°.<br>Printed key: 94°",
    "answers": [
      "94",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14674,
    "id": 25905,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Initial water = 2 × 15 × 15 = 450 cm³.<br>(b) Leak rate: from 600 cm³ (7 a.m.) the reading rose 150 cm³ per hour, so 1 hour = 150 cm³.<br>Full con",
    "answers": [
      "450",
      "3",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14675,
    "id": 25906,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) The number of circles on one side is twice the figure number, so 12 circles per side -> 12 ÷ 2 = Figure 6.<br>(b) The number of squares in Figure ",
    "answers": [
      "6",
      "225",
      "89",
      null
    ],
    "correct_index": null
  },
  {
    "index": 14676,
    "id": 25907,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Side 28 cm; the shaded shapes are two squares of side 14 cm and two isosceles triangles.<br>One small square = 14 × 14 = 196 cm²; two squares = 392 cm",
    "answers": [
      "343",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14677,
    "id": 25908,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Anna keeps 7/9 of her beads; Brenda keeps 3/7 of hers.<br>Setting them equal: 7/9 × Anna = 3/7 × Brenda, so 21/27...<br>gives 49 units (Anna) = 27 uni",
    "answers": [
      "\\(\\dfrac{24}{59}\\)",
      "\\(\\dfrac{216}{531}\\)",
      "\\(\\dfrac{168}{531}\\)",
      "\\(\\dfrac{59}{24}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14678,
    "id": 25909,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Add the place values: 70 000 + 9000 + 200 + 5 = 79 205.",
    "answers": [
      "70 925",
      "79 025",
      "79 205",
      "79 250"
    ],
    "correct_index": 2
  },
  {
    "index": 14679,
    "id": 25910,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "In 458 321 the digit 4 occupies the hundred-thousands place (400 000).",
    "answers": [
      "hundreds",
      "thousands",
      "ten thousands",
      "hundred thousands"
    ],
    "correct_index": 3
  },
  {
    "index": 14680,
    "id": 25911,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Convert to sixths: 7/6, 4/3 = 8/6, 1 1/2 = 9/6.<br>Greatest to smallest: 9/6, 8/6, 7/6, i.e. 1 1/2, 4/3, 7/6.",
    "answers": [
      "\\(\\dfrac{7}{6}\\) , \\(\\dfrac{4}{3}\\) , \\(1\\dfrac{1}{2}\\)",
      "\\(\\dfrac{4}{3}\\) , \\(\\dfrac{7}{6}\\) , \\(1\\dfrac{1}{2}\\)",
      "\\(1\\dfrac{1}{2}\\) , \\(\\dfrac{4}{3}\\) , \\(\\dfrac{7}{6}\\)",
      "\\(1\\dfrac{1}{2}\\) , \\(\\dfrac{7}{6}\\) , \\(\\dfrac{4}{3}\\)"
    ],
    "correct_index": 2
  },
  {
    "index": 14681,
    "id": 25912,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "A typical pear has a mass of about 120 g.<br>12 g is far too light, while 1200 g (1.2 kg) and 12 000 g (12 kg) are far too heavy.",
    "answers": [
      "12 g",
      "120 g",
      "1200 g",
      "12 000 g"
    ],
    "correct_index": 1
  },
  {
    "index": 14682,
    "id": 25913,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "0.10 lies between 0.08 and 0.17.<br>0.01 is too small; 0.18 and 0.90 are too large.",
    "answers": [
      "0.01",
      "0.10",
      "0.18",
      "0.90"
    ],
    "correct_index": 1
  },
  {
    "index": 14683,
    "id": 25914,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "From 2.0 kg to 2.5 kg there are 10 intervals, so each interval is 0.05 kg.<br>A is 4 intervals past 2.5 kg: 2.5 + 4 x 0.05 = 2.70 kg.",
    "answers": [
      "2.70 kg",
      "2.75 kg",
      "2.90 kg",
      "3.00 kg"
    ],
    "correct_index": 0
  },
  {
    "index": 14684,
    "id": 25915,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Volume = length x breadth x height = 5 x 5 x 8 = 200 cm³.",
    "answers": [
      "40 cm³",
      "200 cm³",
      "240 cm³",
      "320 cm³"
    ],
    "correct_index": 1
  },
  {
    "index": 14685,
    "id": 25916,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "48 posters is 48 ÷ 6 = 8 times as many as 6 posters, so it takes 8 x 2 = 16 min.",
    "answers": [
      "8 min",
      "12 min",
      "16 min",
      "24 min"
    ],
    "correct_index": 2
  },
  {
    "index": 14686,
    "id": 25917,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Angles q, r and s lie on one side of the straight line AB at the same point, so they sum to 180°.",
    "answers": [
      "\\(\\angle r = \\angle u\\)",
      "\\(\\angle q + \\angle r = 180°\\)",
      "\\(\\angle q + \\angle r + \\angle s = 180°\\)",
      "\\(\\angle q + \\angle r + \\angle s + \\angle t = 360°\\)"
    ],
    "correct_index": 2
  },
  {
    "index": 14687,
    "id": 25918,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "The hundreds digit is 9 (≥5), so round up: 87 954 rounds to 88 000.",
    "answers": [
      "80 000",
      "87 000",
      "88 000",
      "90 000"
    ],
    "correct_index": 2
  },
  {
    "index": 14688,
    "id": 25919,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Convert to cm: Ali 160 cm, Bala 132 cm, Chenle 145 cm, Danial 150 cm.<br>The tallest is Ali (160 cm).",
    "answers": [
      "Ali",
      "Bala",
      "Chenle",
      "Danial"
    ],
    "correct_index": 0
  },
  {
    "index": 14689,
    "id": 25920,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Purple : yellow = 56 : 24.<br>Dividing both by 8 gives 7 : 3.",
    "answers": [
      "3 : 7",
      "7 : 3",
      "3 : 10",
      "7 : 10"
    ],
    "correct_index": 1
  },
  {
    "index": 14690,
    "id": 25921,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Evaluate: 32÷100 = 0.32, 32÷1000 = 0.032, 320÷100 = 3.2, 320÷1000 = 0.32.<br>The greatest is 320÷100 = 3.2.",
    "answers": [
      "\\(32 \\div 100\\)",
      "\\(32 \\div 1000\\)",
      "\\(320 \\div 100\\)",
      "\\(320 \\div 1000\\)"
    ],
    "correct_index": 2
  },
  {
    "index": 14691,
    "id": 25922,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "2/3 of the number is 12, so 1/3 is 6 and the whole number is 18.<br>Half of 18 is 9.",
    "answers": [
      "8",
      "9",
      "18",
      "4"
    ],
    "correct_index": 1
  },
  {
    "index": 14692,
    "id": 25923,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "The smallest cuboid that contains the solid is 2 x 2 x 2 = 8 unit cubes.<br>The figure shown has 4 cubes, so 8 - 4 = ...<br>(A 2x2x2 cuboid holds 8 cu",
    "answers": [
      "5",
      "7",
      "12",
      "22"
    ],
    "correct_index": 1
  },
  {
    "index": 14693,
    "id": 25924,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Brackets first: 6 + 8 = 14.<br>Then 14 ÷ 2 = 7, 7 x 3 = 21.<br>Finally 50 - 21 = 29.",
    "answers": [
      "29",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14694,
    "id": 25925,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Rate = total volume ÷ time = 28 ℓ ÷ 7 min = 4 ℓ/min.",
    "answers": [
      "4",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14695,
    "id": 25926,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Multiples of 8: 8, 16, 24, 32, 40, 48, 56, 64...<br>The largest one below 60 is 56.",
    "answers": [
      "56",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14696,
    "id": 25927,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "45 ÷ 200 = 45/200.<br>Divide numerator and denominator by 5: 9/40, which is in simplest form.",
    "answers": [
      "\\(\\dfrac{9}{40}\\)",
      "\\(\\dfrac{45}{200}\\)",
      "\\(\\dfrac{9}{20}\\)",
      "\\(\\dfrac{18}{80}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14697,
    "id": 25928,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "5 ÷ 9 = 0.555..., so 4 5/9 = 4.555..., which rounds to 4.56 (2 d.p.).",
    "answers": [
      "4.56",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14698,
    "id": 25929,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Interest = 2% of \\(\\$20\\) 000 = 2/100 x \\(\\$20\\) 000 = \\(\\$400\\).",
    "answers": [
      "400",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14699,
    "id": 25930,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "After Jackson gives 10 chocolates, Kala has 40 + 10 + 10 = 60 more than Jackson.<br>Since Kala = 5 x Jackson, the difference of 4 units = 60, so 1 uni",
    "answers": [
      "15",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14700,
    "id": 25931,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "The right angle is at A, with legs AB = 8 cm and AC = 6 cm.<br>Area = 1/2 x 8 x 6 = 24 cm².",
    "answers": [
      "24",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14701,
    "id": 25932,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Double the first set: 4 pencils + 8 notebooks = \\(\\$52\\). Subtract the second set (4 pencils + 2 notebooks = \\(\\$22\\)): 6 notebooks = \\(\\$30\\), so 1 n",
    "answers": [
      "5",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14702,
    "id": 25933,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total area = 12 units (the largest oval).<br>Unshaded area = 12u - 3u = ...<br>per key: total = 12u, unshaded = 10u - 3u = 7u, so fraction unshaded = ",
    "answers": [
      "\\(\\dfrac{7}{12}\\)",
      "\\(\\dfrac{5}{12}\\)",
      "\\(\\dfrac{3}{12}\\)",
      "\\(\\dfrac{10}{12}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14703,
    "id": 25934,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total time 2.00 to 4.50 pm = 2 h 50 min.<br>First hour = \\(\\$6\\). Remaining 1 h 50 min = 110 min = 4 blocks of 30 min (4 x \\(\\$2.50\\) = \\(\\$10\\)). Tot",
    "answers": [
      "16",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14704,
    "id": 25935,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "After completing rhombus ABCD on the dot grid, the measured angle BAD is 70°.<br>(Key Q29b = 70°.)",
    "answers": [
      "70",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14705,
    "id": 25936,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Angle DEF = 58°, so along straight line DA the angle CFE folds: ∠CFE = 180° - 58° - 90° = 32°.<br>The fold makes ∠AFB = 90° - 32° - 32° = 26°.<br>(Key",
    "answers": [
      "26",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14706,
    "id": 25937,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "There are 12 rectangles in total and 5 are shaded, so the fraction shaded is 5/12.",
    "answers": [
      "\\(\\dfrac{5}{12}\\)",
      "\\(\\dfrac{7}{12}\\)",
      "\\(\\dfrac{5}{7}\\)",
      "\\(\\dfrac{1}{2}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14707,
    "id": 25938,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "VZY is a straight line (180°).<br>At Z there is a right angle (90°) and an angle of 32°.<br>So ∠a = 180° - 90° - 32° = 58°.",
    "answers": [
      "58",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14708,
    "id": 25939,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Tank volume = 35 x 8 x 12 = 3360 cm³.<br>The empty (unfilled) part is 2/5: 2/5 x 3360 = 1344 cm³ = 1344 ml.",
    "answers": [
      "1344",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14709,
    "id": 25940,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "WX is parallel to ZY (trapezium), so co-interior angles ∠XWZ + ∠WZY = 180° — True.<br>For (b): with ∠Y = 120° and WZ = WX, working through the angles ",
    "answers": [
      "(a) True, (b) False",
      "(a) False, (b) True",
      "(a) True, (b) Not possible to tell",
      "(a) Not possible to tell, (b) False"
    ],
    "correct_index": 0
  },
  {
    "index": 14710,
    "id": 25941,
    "type": 2,
    "flags": [
      "ANS0(20)_NOT_IN_SOLUTION"
    ],
    "solution_preview": "Opposite triangles in such a figure have equal areas, and each pair (W+Z and X+Y) is half the rectangle.",
    "answers": [
      "20",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14711,
    "id": 25942,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Before buying, he had 9 - 2 1/2 = 6 1/2 kg.<br>Adding back what he used: 6 1/2 + 4 3/5 = 11 1/10 kg at first.",
    "answers": [
      "\\(11\\dfrac{1}{10}\\) kg",
      "\\(6\\dfrac{1}{2}\\) kg",
      "\\(11\\dfrac{9}{10}\\) kg",
      "\\(7\\dfrac{1}{10}\\) kg"
    ],
    "correct_index": 0
  },
  {
    "index": 14712,
    "id": 25943,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "The 24 extra cars have 24 x 4 = 96 wheels.<br>Remaining 276 - 96 = 180 wheels belong to equal numbers of cars and bicycles.<br>Each car+bicycle set ha",
    "answers": [
      "30",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14713,
    "id": 25944,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "The difference 3.09 - 1.05 = 2.04 kg stays the same and equals 3 units (B is 4 units, A is 1 unit).<br>So 1 unit = 0.68 kg = A after removal.<br>Remov",
    "answers": [
      "0.37",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14714,
    "id": 25945,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total of 6 boys = 6 x 52 = 312 kg.<br>Total of remaining 4 boys = 4 x 48 = 192 kg.<br>The 2 boys who left = 312 - 192 = 120 kg, so their average = 120",
    "answers": [
      "60",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14715,
    "id": 25946,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total pocket money in a week = \\(\\$8\\) x 7 = \\(\\$56\\).<br>She spends \\(\\$5.60\\) x 5 = \\(\\$28\\) on weekdays, so she saves \\(\\$56\\) - \\(\\$28\\) = \\(\\$28\\",
    "answers": [
      "10",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14716,
    "id": 25947,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total = 16 equal units = 80, so 1 unit = 5 students.<br>(a) Badminton + Table Tennis = 10 units = 50 students.<br>(b) Basketball = 30 students; 30/80 ",
    "answers": [
      "50",
      "37.5",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14717,
    "id": 25948,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Make the mango parts equal: Shop A 4:3 x2 = 8:6, Shop B 3:2 x3 = 9:6.<br>Apples differ by 9 - 8 = 1 unit = 70.<br>Shop B total = 9 + 6 = 15 units = 15",
    "answers": [
      "1050",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14718,
    "id": 25949,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Triangle ABG is isosceles (AB = BG) with base angle 65°, so ∠ABG = 180° - 65° - 65° = 50°.<br>(b) ∠DCF = 180° - 112° = 68° (rhombus).<br>In triang",
    "answers": [
      "50",
      "29",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14719,
    "id": 25950,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Discount = 35% of (2 x \\(\\$450\\) = \\(\\$900\\)) = 35/100 x \\(\\$900\\) = \\(\\$315\\).<br>(b) Usual backpack price = 40% x \\(\\$450\\) = \\(\\$180\\).<br>Disc",
    "answers": [
      "315",
      "117",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14720,
    "id": 25951,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Total discount over the original 68 files = 68 x \\(\\$3.40\\) = \\(\\$231.20\\).<br>This pays for 19 extra files less the \\(\\$3.20\\) left: 19 files = \\",
    "answers": [
      "12",
      "1047.20",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14721,
    "id": 25952,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Ali keeps 2/3, Betty keeps 3/5; these are equal.<br>Letting equal leftover = L, Ali = 3/2 L (in units), Betty = 5/3 L; working in units the total is 1",
    "answers": [
      "(a) $3000, (b) $112.50",
      "(a) $2700, (b) $112.50",
      "(a) $3000, (b) $450",
      "(a) $2700, (b) $150"
    ],
    "correct_index": 0
  },
  {
    "index": 14722,
    "id": 25953,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) QRST is a square; area = 4 x area of triangle PRQ = 4 x 16 = 64 cm², so side RQ = 8 cm.<br>(b) Areas: square QRST = 64; triangle SRZ = 1/2 x 8 x 5",
    "answers": [
      "8",
      "278.5",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14723,
    "id": 25954,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Eighty thousand = 80 000; two hundred = 200.<br>So 80 000 + 200 = 80 200.<br>Answer: 80 200.",
    "answers": [
      "8200",
      "80 200",
      "800 200",
      "820 000"
    ],
    "correct_index": 1
  },
  {
    "index": 14724,
    "id": 25955,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "\\(\\dfrac{1}{50}=\\dfrac{2}{100}=0.02\\).<br>So \\(1\\dfrac{1}{50}=1.02\\).<br>Answer: 1.02.",
    "answers": [
      "1.02",
      "1.15",
      "1.2",
      "1.5"
    ],
    "correct_index": 0
  },
  {
    "index": 14725,
    "id": 25956,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "27 words is 3 times 9 words (27 / 9 = 3).<br>Time = 8 x 3 = 24 seconds.<br>Answer: 24 seconds.",
    "answers": [
      "16 seconds",
      "24 seconds",
      "26 seconds",
      "32 seconds"
    ],
    "correct_index": 1
  },
  {
    "index": 14726,
    "id": 25957,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "The clock shows 8.50 (hour hand near 9, minute hand on 10 = 50 min), i.e. 20 50 in 24-hour evening time.<br>15 minutes after 20 50 is 21 05.<br>Answer",
    "answers": [
      "20 35",
      "20 50",
      "21 05",
      "22 58"
    ],
    "correct_index": 2
  },
  {
    "index": 14727,
    "id": 25958,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Volume = length x breadth x height = 5 x 5 x 2 = 50 cm³.<br>Answer: 50 cm³.",
    "answers": [
      "10 cm³",
      "20 cm³",
      "50 cm³",
      "100 cm³"
    ],
    "correct_index": 2
  },
  {
    "index": 14728,
    "id": 25959,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Each grid square is 1 cm.<br>Tracing the outline of each shape, Figure A (the notched/U-shape) has the longest boundary.<br>Answer: Figure A.",
    "answers": [
      "Figure A",
      "Figure B",
      "Figure C",
      "Figure D"
    ],
    "correct_index": 0
  },
  {
    "index": 14729,
    "id": 25960,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "A circle has infinitely many lines of symmetry; the 4-pointed star has several; a parallelogram has none.<br>The arrow has exactly one line of symmetr",
    "answers": [
      "Circle",
      "Four-pointed star",
      "Arrow",
      "Parallelogram"
    ],
    "correct_index": 2
  },
  {
    "index": 14730,
    "id": 25961,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Three lines pass through the point.<br>∠a and ∠c are vertically opposite angles (∠a between R and the upper line; ∠c between S and the lower line), so",
    "answers": [
      "∠a = ∠c",
      "∠b = ∠e",
      "∠a + ∠c = 180°",
      "∠a + ∠b + ∠c = 180°"
    ],
    "correct_index": 0
  },
  {
    "index": 14731,
    "id": 25962,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Rounded to the nearest hundred gives 24 000 means the number lies in 23 950 to 24 049.<br>Of the options, only 24 009 rounds to 24 000.<br>(23 099 to ",
    "answers": [
      "23 099",
      "23 940",
      "24 009",
      "24 050"
    ],
    "correct_index": 2
  },
  {
    "index": 14732,
    "id": 25963,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "The figure that has exactly one third of its area shaded is option (4).<br>Answer: option (4).",
    "answers": [
      "Cross of 5 squares with 1 shaded",
      "Square with a shaded triangle",
      "Hexagon split into 6 triangles, 2 shaded",
      "Figure of squares with one shaded"
    ],
    "correct_index": 3
  },
  {
    "index": 14733,
    "id": 25964,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Footballs = 15% of 40 = 6.<br>Volleyballs = 35% of 40 = 14.<br>Rest = 40 - 6 - 14 = 20, split equally so basketballs = 10.<br>Footballs + basketballs ",
    "answers": [
      "10",
      "16",
      "20",
      "26"
    ],
    "correct_index": 1
  },
  {
    "index": 14734,
    "id": 25965,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total mass = 3 x 55 = 165 kg.<br>John + Angel = 165 - 56 = 109 kg.<br>With John - Angel = 11: John = (109 + 11) / 2 = 60 kg (Angel = 49 kg).<br>Answer",
    "answers": [
      "54.5 kg",
      "60 kg",
      "98 kg",
      "100 kg"
    ],
    "correct_index": 1
  },
  {
    "index": 14735,
    "id": 25966,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Cubes may be added only where they do not change the top view or front view outline.<br>Filling the hidden gaps behind the visible solid allows up to ",
    "answers": [
      "1",
      "2",
      "3",
      "5"
    ],
    "correct_index": 3
  },
  {
    "index": 14736,
    "id": 25967,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Square perimeter = 4 x 0.2 = 0.8 m.<br>Triangle perimeter = 3 x 0.24 = 0.72 m.<br>Total = 0.8 + 0.72 = 1.52 m.<br>Answer: 1.52 m.",
    "answers": [
      "0.08 m",
      "0.44 m",
      "0.76 m",
      "1.52 m"
    ],
    "correct_index": 3
  },
  {
    "index": 14737,
    "id": 25968,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "In triangle ABC each angle is 60°.<br>At O, ∠OAS = 34° (given at A), and ∠ASC (in triangle ASC with ∠ACS = 60°) gives ∠ASB.<br>∠BSP works out to 94°.<",
    "answers": [
      "34°",
      "86°",
      "94°",
      "146°"
    ],
    "correct_index": 2
  },
  {
    "index": 14738,
    "id": 25969,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "2.4 ÷ 200 = 2.4 ÷ 2 ÷ 100 = 1.2 ÷ 100 = 0.012.<br>Answer: 0.012.",
    "answers": [
      "0.012",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14739,
    "id": 25970,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "18% of 600 = 0.18 x 600 = 108.<br>Answer: 108.",
    "answers": [
      "108",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14740,
    "id": 25971,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "\\(\\dfrac{4}{7}\\times\\dfrac{49}{16}=\\dfrac{4\\times49}{7\\times16}=\\dfrac{7}{4}=1\\dfrac{3}{4}\\).<br>Answer: \\(1\\dfrac{3}{4}\\).",
    "answers": [
      "\\(1\\dfrac{3}{4}\\)",
      "\\(1\\dfrac{1}{4}\\)",
      "\\(2\\dfrac{1}{4}\\)",
      "\\(\\dfrac{7}{4}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14741,
    "id": 25972,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Lily starts facing the Staff Room (south).<br>A 1/4-turn (90°) right faces her to the Science Garden.<br>A 225° anticlockwise turn from there (225° = ",
    "answers": [
      "Basketball Court",
      "Foyer",
      "Library",
      "Computer Lab"
    ],
    "correct_index": 0
  },
  {
    "index": 14742,
    "id": 25973,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "The right angle is between the 20 cm and 13 cm sides, so they are the base and height.<br>Area = 1/2 x 20 x 13 = 130 cm².<br>Answer: 130 cm².",
    "answers": [
      "130",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14743,
    "id": 25974,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) 40 − (20 − 4) ÷ 4 × 3 = 40 − 16 ÷ 4 × 3 = 40 − 4 × 3 = 40 − 12 = 28.<br>(b) Multiples of 8: ..., 48, 56, 64.<br>The largest below 60 is 56.<br>Ans",
    "answers": [
      "28",
      "56",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14744,
    "id": 25975,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "\\(2-\\dfrac{2}{3}-\\dfrac{1}{6}=2-\\dfrac{4}{6}-\\dfrac{1}{6}=2-\\dfrac{5}{6}=1\\dfrac{1}{6}\\).<br>Answer: \\(1\\dfrac{1}{6}\\).",
    "answers": [
      "\\(1\\dfrac{1}{6}\\)",
      "\\(1\\dfrac{1}{2}\\)",
      "\\(\\dfrac{5}{6}\\)",
      "\\(1\\dfrac{5}{6}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14745,
    "id": 25976,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "7.68 + 3.40 = 11.08.<br>Answer: 11.08.",
    "answers": [
      "11.08",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14746,
    "id": 25977,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Convert all to kg: 3.055 kg; 3 kg 250 g = 3.25 kg; \\(3\\dfrac{1}{8}\\) kg = 3.125 kg.<br>Heaviest to lightest: 3.25 > 3.125 > 3.055, i.e. 3 kg 250 g, \\(",
    "answers": [
      "3 kg 250 g, \\(3\\dfrac{1}{8}\\) kg, 3.055 kg",
      "3.055 kg, \\(3\\dfrac{1}{8}\\) kg, 3 kg 250 g",
      "\\(3\\dfrac{1}{8}\\) kg, 3 kg 250 g, 3.055 kg",
      "3 kg 250 g, 3.055 kg, \\(3\\dfrac{1}{8}\\) kg"
    ],
    "correct_index": 0
  },
  {
    "index": 14747,
    "id": 25978,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "The jug is marked up to 2 ℓ.<br>The water level reads 1800 mℓ (i.e. 1.8 ℓ).<br>Answer: 1800 mℓ.",
    "answers": [
      "1800",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14748,
    "id": 25979,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Reading the line graph at 08 10 gives 64°C.<br>(b) The temperature is 80°C and above from 08 15 to 08 35, a span of 20 minutes.<br>Answers: 64°C; ",
    "answers": [
      "64",
      "20",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14749,
    "id": 25980,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "1 bracelet = 205 ÷ 5 = 41 cm.<br>16 bracelets = 41 x 16 = 656 cm = 6.56 m.<br>Answer: 6.56 m.",
    "answers": [
      "6.56",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14750,
    "id": 25981,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) On the 1 cm grid, base EF = 2 cm and height (from B down to line FC) = 4 cm, so area = 1/2 x 2 x 4 = 4 cm².<br>(b) Triangle BEC shares the same ba",
    "answers": [
      "4",
      "BEC",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14751,
    "id": 25982,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total age = 10 x 35 = 350.<br>After the 53-year-old leaves: 350 − 53 = 297 for 9 members.<br>Average = 297 ÷ 9 = 33 years.<br>Answer: 33 years.",
    "answers": [
      "33",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14752,
    "id": 25983,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total money = 80 + 45 = 125.<br>Percentage spent = 80/125 x 100% = 64%.<br>Answer: 64%.",
    "answers": [
      "64",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14753,
    "id": 25984,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Let big bags = b.<br>The 30 extra small bags hold 30 x 4 = 120 cookies.<br>Remaining cookies = 2360 − 120 = 2240, shared by equal numbers of small and",
    "answers": [
      "224",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14754,
    "id": 25985,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "When the rectangle is folded, the fold maps the corner so the angle at Y is 56°.<br>Using the fold symmetry and the straight angle / corner of the rec",
    "answers": [
      "118",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14755,
    "id": 25986,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Left: 1/5 C + 1/4 S = 736.<br>Also 4/5 C + 3/4 S = 3262 − 736 = 2526.<br>From total C + S = 3262.<br>Working as in the key: 1/5 C = 318, so C = 1590; ",
    "answers": [
      "1272",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14756,
    "id": 25987,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "a, b, c lie on the straight line PQ, so they sum to 180°.<br>Total units = 2 + 6 + 1 = 9; 1 unit = 180° ÷ 9 = 20°.<br>Largest = 6 x 20 = 120°, smalles",
    "answers": [
      "160",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14757,
    "id": 25988,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Blue − green = 5 − 2 = 3 units = 42, so 1 unit = 14.<br>Total units = 6 + 5 + 2 = 13; total marbles = 13 x 14 = 182.<br>Answer: 182 marbles.",
    "answers": [
      "182",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14758,
    "id": 25989,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "50 g package = 80 cents.<br>370 g package: first 100 g = \\(\\$1.20\\), then 3 additional 100 g steps (to cover up to 400 g) at \\(\\$1.20\\) each = \\(\\$1.2",
    "answers": [
      "5.60",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14759,
    "id": 25990,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "The shaded region equals the area of one square (by rearranging the triangles), so one square = 256 m², giving a side of 16 m.<br>AC spans two square ",
    "answers": [
      "32",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14760,
    "id": 25991,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Discount = 15% x \\(\\$6000\\) = \\(\\$900\\).<br>(b) Discounted price = \\(\\$6000\\) − \\(\\$900\\) = \\(\\$5100\\). With 8% GST: \\(\\$5100\\) x 108% = \\(\\$5508\\",
    "answers": [
      "900",
      "5508",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14761,
    "id": 25992,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Difference stays constant: 1090 − 320 = 770.<br>After joining, A = 3 x B, so the difference = 2 units = 770, giving 1 unit (new Zoo B) = 385.<br>Anima",
    "answers": [
      "65",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14762,
    "id": 25993,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "In triangle at the top: 180° − 29° − 32° = 119°, so its base angle = 180° − 119° = 61°.<br>In the other triangle: 180° − 31° − 42° = 107°, base angle ",
    "answers": [
      "46",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14763,
    "id": 25994,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Tank volume = 54 x 16 x 24 = 20736 cm³.<br>(a) 1/4-filled = 5184 cm³; half-filled = 10368 cm³.<br>Water added by 8 pails = 10368 − 5184 = 5184 cm³, so",
    "answers": [
      "648",
      "9",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14764,
    "id": 25995,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total 360 in 11 : 4 means 15 units = 360, 1 unit = 24.<br>Black = 4 x 24 = 96; green + red = 11 x 24 = 264.<br>Red = 20% x 360 = 72; green = 264 − 72 ",
    "answers": [
      "7 : 8",
      "8 : 7",
      "4 : 11",
      "3 : 5"
    ],
    "correct_index": 0
  },
  {
    "index": 14765,
    "id": 25996,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Apples + oranges = 336 x 2 = 672.<br>With oranges − apples = 140: oranges = (672 + 140) ÷ 2 = 406.<br>(b) Original total of 3 fruits = 332 x 3 = 9",
    "answers": [
      "406",
      "382",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14766,
    "id": 25997,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Use 42 of the \\(\\$4.20\\) bundles (42 boxes + 42 sticks) = 42 x \\(\\$4.20\\) = \\(\\$176.40\\). Remaining: 1 box + 6 sticks. Best for the leftover: 1 box (\\",
    "answers": [
      "189.05",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14767,
    "id": 25998,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Overlap = 18 x 18 = 324 cm².<br>Unshaded (the two non-overlapping parts) = 2214 cm².<br>Following the key: 2214 − 324 = 1890; 1890 ÷ 3 = 630; 630 x 2 ",
    "answers": [
      "2450",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14768,
    "id": 25999,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Let original rows = r.<br>Original chairs = 10r.<br>New chairs = 10r + 24 = 12(r − 6) = 12r − 72.<br>So 10r + 24 = 12r − 72, giving 2r = 96, r = 48 ro",
    "answers": [
      "480",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14769,
    "id": 26000,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Copies = sales ÷ price.<br>Sports = 1950 ÷ 6 = 325; Science = 1448 ÷ 4 = 362; Math = 1850 ÷ 5 = 370.<br>Math sold the most copies.<br>(b) Total sa",
    "answers": [
      "Math",
      "1312",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14770,
    "id": 26001,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Pages 1-9: 9 x 1 = 9 digits.<br>Pages 10-99: 90 x 2 = 180 digits.<br>Total = 9 + 180 = 189 digits.<br>(b) Remaining digits = 612 − 189 = 423, all ",
    "answers": [
      "189",
      "240",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14771,
    "id": 26002,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Mandy + Nora's extra = 34 + 20 = 54, which equals 9 equal parts of the remaining-after-Penny (Olivia 1 part, Nora-extra aside, Mandy parts).<br>Follow",
    "answers": [
      "120",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14772,
    "id": 26003,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Place values after the decimal point: 6 is tenths, 8 is hundredths, 7 is thousandths.<br>So the hundredths digit is 8.",
    "answers": [
      "5",
      "6",
      "7",
      "8"
    ],
    "correct_index": 3
  },
  {
    "index": 14773,
    "id": 26004,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "1 kg = 1000 g, so 52 g = 0.052 kg.<br>Therefore 23 kg 52 g = 23.052 kg.",
    "answers": [
      "23.025 kg",
      "23.052 kg",
      "23.502 kg",
      "23.520 kg"
    ],
    "correct_index": 1
  },
  {
    "index": 14774,
    "id": 26005,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "42 : 28 : 14.<br>Divide each term by the common factor 14: 42 ÷ 14 = 3, 28 ÷ 14 = 2, 14 ÷ 14 = 1.<br>So the ratio is 3 : 2 : 1.",
    "answers": [
      "2 : 3 : 1",
      "2 : 4 : 6",
      "3 : 2 : 1",
      "6 : 4 : 2"
    ],
    "correct_index": 2
  },
  {
    "index": 14775,
    "id": 26006,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "In 60 seconds (1 minute) it seals 120 packets.<br>30 minutes × 120 = 3600 packets.",
    "answers": [
      "3600",
      "360",
      "60",
      "40"
    ],
    "correct_index": 0
  },
  {
    "index": 14776,
    "id": 26007,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Fraction given = \\(\\dfrac{60}{240}=\\dfrac{1}{4}\\).<br>As a percentage, \\(\\dfrac{1}{4}\\times 100\\% = 25\\%\\).",
    "answers": [
      "20%",
      "25%",
      "75%",
      "80%"
    ],
    "correct_index": 1
  },
  {
    "index": 14777,
    "id": 26008,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "35% of \\(\\$1200\\) = \\(\\dfrac{35}{100}\\times 1200 = 420\\). He spent \\(\\$420\\) on food.",
    "answers": [
      "$180",
      "$360",
      "$420",
      "$780"
    ],
    "correct_index": 2
  },
  {
    "index": 14778,
    "id": 26009,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Line AB slopes downwards from upper-right to lower-left.<br>Comparing the grid slopes of the other lines, JK has the same slope (same horizontal and v",
    "answers": [
      "CD",
      "EF",
      "GH",
      "JK"
    ],
    "correct_index": 3
  },
  {
    "index": 14779,
    "id": 26010,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Triangle ABD has base AD = 15 cm and the perpendicular height AB = 7 cm.<br>Area = \\(\\dfrac{1}{2}\\times 15\\times 7 = 52.5\\) cm².",
    "answers": [
      "42 cm²",
      "52.5 cm²",
      "54 cm²",
      "84 cm²"
    ],
    "correct_index": 1
  },
  {
    "index": 14780,
    "id": 26011,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Inspecting the six marked angles in the concave figure, only 2 of them open wider than a right angle (more than 90°).<br>The rest are 90° or less.",
    "answers": [
      "6",
      "2",
      "3",
      "4"
    ],
    "correct_index": 1
  },
  {
    "index": 14781,
    "id": 26012,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Counting the unit cubes in the staircase solid (including the hidden ones supporting the upper cubes) gives a total of 10 unit cubes.",
    "answers": [
      "10",
      "12",
      "15",
      "17"
    ],
    "correct_index": 0
  },
  {
    "index": 14782,
    "id": 26013,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "As decimals: \\(\\dfrac{3}{7}\\approx 0.43\\), \\(\\dfrac{4}{5}=0.8\\), \\(\\dfrac{8}{9}\\approx 0.89\\).<br>Smallest to largest: \\(\\dfrac{3}{7},\\ \\dfrac{4}{5},\\",
    "answers": [
      "\\(\\dfrac{8}{9},\\ \\dfrac{3}{7},\\ \\dfrac{4}{5}\\)",
      "\\(\\dfrac{8}{9},\\ \\dfrac{4}{5},\\ \\dfrac{3}{7}\\)",
      "\\(\\dfrac{3}{7},\\ \\dfrac{4}{5},\\ \\dfrac{8}{9}\\)",
      "\\(\\dfrac{3}{7},\\ \\dfrac{8}{9},\\ \\dfrac{4}{5}\\)"
    ],
    "correct_index": 2
  },
  {
    "index": 14783,
    "id": 26014,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total = 23 + 23 + 18 + 16 + 0 = 80.<br>Average = 80 ÷ 5 = 16.",
    "answers": [
      "23",
      "20",
      "18",
      "16"
    ],
    "correct_index": 3
  },
  {
    "index": 14784,
    "id": 26015,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "1505 kg ÷ 50 = 30.1 kg per pack.",
    "answers": [
      "30.1 kg",
      "31 kg",
      "300.1 kg",
      "301 kg"
    ],
    "correct_index": 0
  },
  {
    "index": 14785,
    "id": 26016,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Children = \\(\\dfrac{2}{3}\\times 270 = 180\\).<br>Boys = \\(\\dfrac{3}{5}\\) of the children = \\(\\dfrac{3}{5}\\times 180 = 108\\).",
    "answers": [
      "180",
      "162",
      "108",
      "72"
    ],
    "correct_index": 2
  },
  {
    "index": 14786,
    "id": 26017,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "200 × 0.78 ℓ = 156 ℓ.",
    "answers": [
      "14.6 ℓ",
      "15.6 ℓ",
      "146 ℓ",
      "156 ℓ"
    ],
    "correct_index": 3
  },
  {
    "index": 14787,
    "id": 26018,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Work inside the brackets first: \\(8\\div 4\\times 2 = 2\\times 2 = 4\\), so \\(35 + 4 = 39\\).<br>Then \\(35\\div 7 = 5\\).<br>So \\(198 + 5 - 39 = 203 - 39 = 1",
    "answers": [
      "164",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14788,
    "id": 26019,
    "type": 2,
    "flags": [
      "VERY_SHORT(21chars)"
    ],
    "solution_preview": "\\(5 \\div 8 = 0.625\\).",
    "answers": [
      "0.625",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14789,
    "id": 26020,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "40 ÷ 5 = 8, so each term on the right is 8 times the left.<br>24 ÷ 8 = 3.<br>The missing number is 3.",
    "answers": [
      "3",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14790,
    "id": 26021,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "AOD is a straight line: \\(\\angle AOB + \\angle BOC + \\angle COD = 180°\\), so \\(\\angle COD = 180 - 90 - 58 = 32°\\).<br>COF is a straight line: \\(\\angle ",
    "answers": [
      "72",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14791,
    "id": 26022,
    "type": 2,
    "flags": [
      "EMPTY_SOLUTION"
    ],
    "solution_preview": "",
    "answers": [
      "72",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14792,
    "id": 26023,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "BCE is a straight line, so \\(\\angle BCD = 180 - 134 = 46°\\).<br>In a rhombus, opposite angles are equal and adjacent angles are supplementary, so \\(\\a",
    "answers": [
      "67",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14793,
    "id": 26024,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "\\(\\dfrac{2}{3}\\times\\dfrac{5}{8}=\\dfrac{10}{24}=\\dfrac{5}{12}\\) (dividing top and bottom by 2).",
    "answers": [
      "\\(\\dfrac{5}{12}\\)",
      "\\(\\dfrac{10}{24}\\)",
      "\\(\\dfrac{7}{12}\\)",
      "\\(\\dfrac{5}{24}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14794,
    "id": 26025,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Volume of a cuboid = length × breadth × height = 23 × 6 × 5 = 690 cm³.",
    "answers": [
      "690",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14795,
    "id": 26026,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Group X = 57, Group Y = 33, Group Z = 75.<br>Highest = 75, lowest = 33.<br>Difference = 75 − 33 = 42.",
    "answers": [
      "42",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14796,
    "id": 26027,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Replace each marker with (pencil + \\(\\$1.20\\)): 3 pencils + 7 pencils + 7 × \\(\\$1.20\\) = \\(\\$87.40\\). So 10 pencils + \\(\\$8.40\\) = \\(\\$87.40\\), giving",
    "answers": [
      "79",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14797,
    "id": 26028,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Larger number = 3069 ÷ 9 = 341.<br>Rounded to the nearest hundred, 341 ≈ 300.",
    "answers": [
      "300",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14798,
    "id": 26029,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "GST = 8% of \\(\\$2800\\) = \\(\\dfrac{8}{100}\\times 2800 = 224\\). Price after GST = \\(\\$2800\\) + \\(\\$224\\) = \\(\\$3024\\).",
    "answers": [
      "3024",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14799,
    "id": 26030,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Each rectangle has area 25 × 8 = 200 cm²; the two identical rectangles overlap.<br>The shaded part is made of two triangles whose areas together equal",
    "answers": [
      "200",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14800,
    "id": 26031,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total height = 154 × 3 = 462 cm.<br>Abel (the shortest) = 146 cm, so Bernard + Carl = 462 − 146 = 316 cm.<br>Carl is taller than Bernard and both are ",
    "answers": [
      "159",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14801,
    "id": 26032,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "\\(5\\dfrac{2}{5}=5.4\\), \\(1\\dfrac{3}{4}=1.75\\), \\(\\dfrac{4}{10}=0.4\\).<br>Left = \\(5.4 - 1.75 - 0.4 = 3.25 = 3\\dfrac{1}{4}\\) m.",
    "answers": [
      "\\(3\\dfrac{1}{4}\\)",
      "\\(3\\dfrac{3}{4}\\)",
      "\\(3\\dfrac{1}{2}\\)",
      "\\(2\\dfrac{3}{4}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14802,
    "id": 26033,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "\\(1\\dfrac{7}{9}=\\dfrac{16}{9}\\).<br>\\(6\\times\\dfrac{16}{9}=\\dfrac{96}{9}=10\\dfrac{6}{9}=10\\dfrac{2}{3}\\) litres.",
    "answers": [
      "\\(10\\dfrac{2}{3}\\)",
      "\\(10\\dfrac{6}{9}\\)",
      "\\(6\\dfrac{7}{9}\\)",
      "\\(9\\dfrac{1}{3}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14803,
    "id": 26034,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total of 5 children = 5 × 48 = 240 kg.<br>Total of 6 people = 6 × 45 = 270 kg.<br>Peter's mass = 270 − 240 = 30 kg.",
    "answers": [
      "30",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14804,
    "id": 26035,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "A, F and E lie on a straight line.<br>At F, \\(\\angle AFB + \\angle BFD + \\angle DFE = 180°\\).<br>Triangle ABF is isosceles (AB = BF) so \\(\\angle BAF = ",
    "answers": [
      "128",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14805,
    "id": 26036,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Let the number of friends be n.<br>Yellow length = 1.4n + 0.6.<br>Red length = 1.8n − 2.2 (she is 2.2 m short).<br>The ribbons are the same length: 1.",
    "answers": [
      "7",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14806,
    "id": 26037,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Double the first set: 4 files + 6 markers = \\(\\$30\\). Compare with 5 files + 6 markers = \\(\\$34.80\\).<br>The difference is 1 file = \\(\\$34.80\\) − \\(\\$",
    "answers": [
      "1.80",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14807,
    "id": 26038,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) 70% were boys, so 30% were girls.<br>Girls = \\(\\dfrac{30}{100}\\times 560 = 168\\).<br>(b) Girls supporting Team A = 168 − 42 = 126.<br>Percentage =",
    "answers": [
      "168",
      "75",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14808,
    "id": 26039,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Peter : Jason difference = 9 − 5 = 4 units = \\(\\$128\\), so 1 unit = \\(\\$32\\).<br>Peter − Chris = 9 − 2 = 7 units = 7 × \\(\\$32\\) = \\(\\$224\\).",
    "answers": [
      "224",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14809,
    "id": 26040,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Let there be n students.<br>Total marks = 74n.<br>Top 3 total = 87 + 95 + 100 = 282.<br>The remaining (n − 3) students average 62: 74n − 282 = 62(n − ",
    "answers": [
      "8",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14810,
    "id": 26041,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Chocolate = \\(\\dfrac{1}{3}\\times 2535 = 845\\).<br>Remaining = 2535 − 845 = 1690.<br>Vanilla = \\(\\dfrac{3}{5}\\times 1690 = 1014\\).<br>(b) 1014 = 30",
    "answers": [
      "1014",
      "35",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14811,
    "id": 26042,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Rectangular tank volume = 19 × 14 × 15 = 3990 cm³.<br>Water = \\(\\dfrac{2}{3}\\times 3990 = 2660\\) cm³.<br>(b) Cubical tank volume = 15 × 15 × 15 = ",
    "answers": [
      "2660",
      "0.04",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14812,
    "id": 26043,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Let each girl start with x stickers.<br>Keryn left = x − 352, Carol left = x − 84, and Carol = 5 × Keryn: x − 84 = 5(x − 352).<br>So x − 84 = 5x − 176",
    "answers": [
      "67",
      "419",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14813,
    "id": 26044,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) DG = GC means G is the midpoint of DC, so DG = 16 cm.<br>Triangle BDG has base DG = 16 cm and height = side AB = 32 cm: area = \\(\\dfrac{1}{2}\\time",
    "answers": [
      "256",
      "512",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14814,
    "id": 26045,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "B, O and C lie on a straight line, so \\(\\angle AOB = 180 - 127 = 53°\\).<br>(a) On the straight line BOC, \\(\\angle AOB + \\angle AOD + \\angle DOC = 180°",
    "answers": [
      "77",
      "74",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14815,
    "id": 26046,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) 9.30 a.m.<br>to 11.45 a.m.<br>= 2 h 15 min.<br>First hour = \\(\\$1.20\\). Remaining 1 h 15 min = 3 half-hour blocks (part thereof) × \\(\\$1.00\\) = \\(",
    "answers": [
      "4.20",
      "5.00",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14816,
    "id": 26047,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "The total number of squares in Figure n is \\((n+1)^2\\): 4, 9, 16, 25, 36, ...<br>(a) White squares increase by 2, 4, 4, 6, 6, ...<br>: 2, 4, 8, 12, 18",
    "answers": [
      "18",
      "40",
      "2500",
      null
    ],
    "correct_index": null
  },
  {
    "index": 14817,
    "id": 26048,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "The digit 3 is in the ten-thousands place, so its value is 30 000.<br>Answer: 30 000.",
    "answers": [
      "30",
      "300",
      "3000",
      "30 000"
    ],
    "correct_index": 3
  },
  {
    "index": 14818,
    "id": 26049,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "\\(\\dfrac{1}{50}=\\dfrac{2}{100}=0.02\\), so \\(1\\dfrac{1}{50}=1.02\\).<br>Answer: 1.02.",
    "answers": [
      "1.1",
      "1.2",
      "1.02",
      "1.15"
    ],
    "correct_index": 2
  },
  {
    "index": 14819,
    "id": 26050,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Figure 3 is a 3x3 grid (9 cells) with...<br>the correct figure showing exactly one quarter shaded is option 3.<br>Answer: option 3.",
    "answers": [
      "Figure 1",
      "Figure 2",
      "Figure 3",
      "Figure 4"
    ],
    "correct_index": 2
  },
  {
    "index": 14820,
    "id": 26051,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "There are 11 apples in total; 6 are unshaded (white).<br>Fraction unshaded = \\(\\dfrac{6}{11}\\).<br>Answer: \\(\\dfrac{6}{11}\\).",
    "answers": [
      "\\(\\dfrac{1}{2}\\)",
      "\\(\\dfrac{5}{6}\\)",
      "\\(\\dfrac{5}{11}\\)",
      "\\(\\dfrac{6}{11}\\)"
    ],
    "correct_index": 3
  },
  {
    "index": 14821,
    "id": 26052,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Using twelfths: \\(\\dfrac{11}{12}, \\dfrac{3}{4}=\\dfrac{9}{12}, \\dfrac{2}{3}=\\dfrac{8}{12}\\).<br>Largest to smallest: \\(\\dfrac{11}{12}, \\dfrac{3}{4}, \\d",
    "answers": [
      "\\(\\dfrac{11}{12}, \\dfrac{2}{3}, \\dfrac{3}{4}\\)",
      "\\(\\dfrac{11}{12}, \\dfrac{3}{4}, \\dfrac{2}{3}\\)",
      "\\(\\dfrac{3}{4}, \\dfrac{2}{3}, \\dfrac{11}{12}\\)",
      "\\(\\dfrac{3}{4}, \\dfrac{11}{12}, \\dfrac{2}{3}\\)"
    ],
    "correct_index": 1
  },
  {
    "index": 14822,
    "id": 26053,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "The height is the perpendicular distance from the opposite vertex C to base AB (or its extension).<br>CD is drawn perpendicular to AB, so the height i",
    "answers": [
      "AE",
      "AF",
      "CD",
      "EB"
    ],
    "correct_index": 2
  },
  {
    "index": 14823,
    "id": 26054,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "On the square grid, line CD has a particular slope; AF has the same slope (same direction), so AF is parallel to CD.<br>Answer: AF.",
    "answers": [
      "AF",
      "BC",
      "BE",
      "DE"
    ],
    "correct_index": 0
  },
  {
    "index": 14824,
    "id": 26055,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Examining the five marked angles of the pentagon-like figure, three of them are acute (less than 90°).<br>Answer: 3.",
    "answers": [
      "5",
      "2",
      "3",
      "4"
    ],
    "correct_index": 2
  },
  {
    "index": 14825,
    "id": 26056,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Brackets first: 6+12 = 18.<br>Then 18 ÷ 2 = 9, 9 × 3 = 27.<br>Finally 30 - 27 = 3.<br>Answer: 3.",
    "answers": [
      "18",
      "2",
      "3",
      "27"
    ],
    "correct_index": 2
  },
  {
    "index": 14826,
    "id": 26057,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "20 minutes is 4 times 5 minutes, so 4 × 10 = 40 stars.<br>Answer: 40.",
    "answers": [
      "10",
      "40",
      "50",
      "200"
    ],
    "correct_index": 1
  },
  {
    "index": 14827,
    "id": 26058,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "The interval from 6 to 7 is divided into 8 equal parts of 0.125 each...<br>A sits at the 6th mark (6 of 8 between 6 and 7): 6 + 6×0.125 = 6.75.<br>Ans",
    "answers": [
      "6.60",
      "6.75",
      "7.20",
      "7.25"
    ],
    "correct_index": 1
  },
  {
    "index": 14828,
    "id": 26059,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Side of square base = 36 ÷ 4 = 9 cm.<br>Volume = 9 × 9 × 10 = 810 cm³.<br>Answer: 810 cm³.",
    "answers": [
      "60 cm³",
      "90 cm³",
      "360 cm³",
      "810 cm³"
    ],
    "correct_index": 3
  },
  {
    "index": 14829,
    "id": 26060,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "In triangle ABC, ∠ACB = 65° and ∠A = 35°, so ∠ABC = 180°-35°-65° = 80°.<br>∠BDC (exterior/using the marked angles) works out to 37°.<br>Answer: 37° (k",
    "answers": [
      "37°",
      "43°",
      "65°",
      "80°"
    ],
    "correct_index": 0
  },
  {
    "index": 14830,
    "id": 26061,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Remaining plants = 12 - 5 = 7.<br>Soil needed = 7 × \\(\\dfrac{3}{8}\\) = \\(\\dfrac{21}{8}\\) = \\(2\\dfrac{5}{8}\\) kg.<br>Answer: \\(2\\dfrac{5}{8}\\) kg.",
    "answers": [
      "\\(1\\dfrac{7}{8}\\) kg",
      "\\(2\\dfrac{5}{8}\\) kg",
      "\\(4\\dfrac{1}{2}\\) kg",
      "\\(4\\dfrac{5}{8}\\) kg"
    ],
    "correct_index": 1
  },
  {
    "index": 14831,
    "id": 26062,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Let starting amount = m.<br>After spending: Ally = m-20, Bella = m-80, and m-20 = 3(m-80).<br>So m-20 = 3m-240, 220 = 2m, m = 110.<br>Bella had \\(\\$11",
    "answers": [
      "$100",
      "$110",
      "$140",
      "$220"
    ],
    "correct_index": 1
  },
  {
    "index": 14832,
    "id": 26063,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Common multiples of 3 and 4 are multiples of 12: 12, 24, 36, ...<br>Those smaller than 30 are 12 and 24.<br>Answer: 12, 24.",
    "answers": [
      "12",
      "24",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14833,
    "id": 26064,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "0.45 × 80 = 36.<br>Answer: 36.",
    "answers": [
      "36",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14834,
    "id": 26065,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "480 ml = 0.48 ℓ.<br>1.05 ℓ - 0.48 ℓ = 0.57 ℓ.<br>Answer: 0.57 ℓ.",
    "answers": [
      "0.57",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14835,
    "id": 26066,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "\\(\\dfrac{2}{3} \\times \\dfrac{4}{9} = \\dfrac{2\\times4}{3\\times9} = \\dfrac{8}{27}\\).<br>Answer: \\(\\dfrac{8}{27}\\).",
    "answers": [
      "\\(\\dfrac{8}{27}\\)",
      "\\(\\dfrac{6}{12}\\)",
      "\\(\\dfrac{8}{12}\\)",
      "\\(\\dfrac{2}{9}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14836,
    "id": 26067,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "∠AFE = 72° (given).<br>∠DFB = ∠AFE = 72° (vertically opposite).<br>∠BFC = 9°, so ∠CFD = 72° - 9° = 63°.<br>Answer: 63°.",
    "answers": [
      "63",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14837,
    "id": 26068,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Reading the graph at 2 min gives 240 bottles.<br>(b) Reading across at 960 bottles gives 8 min.<br>Answers: (a) 240, (b) 8 min.",
    "answers": [
      "240",
      "8",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14838,
    "id": 26069,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "From 7.30 p.m.<br>to 9.30 p.m.<br>is 2 h; to 9.15 p.m.<br>is 1 h 45 min.<br>Answer: 1 h 45 min.",
    "answers": [
      "1",
      "45",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14839,
    "id": 26070,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Counting all the unit cubes that make up Solid A (including hidden cubes) gives 16.<br>Answer: 16.",
    "answers": [
      "16",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14840,
    "id": 26071,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "18 : 24 : 42, divide each by the HCF 6 → 3 : 4 : 7.<br>Answer: 3 : 4 : 7.",
    "answers": [
      "3 : 4 : 7",
      "18 : 24 : 42",
      "9 : 12 : 21",
      "6 : 8 : 14"
    ],
    "correct_index": 0
  },
  {
    "index": 14841,
    "id": 26072,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total = 18 + 24 + 42 = 84.<br>Average = 84 ÷ 3 = 28.<br>Answer: 28.",
    "answers": [
      "28",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14842,
    "id": 26073,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "15% of 40 = \\(\\dfrac{15}{100} \\times 40\\) = 6.<br>Answer: 6.",
    "answers": [
      "6",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14843,
    "id": 26074,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Deposited = 8000 - 2000 = \\(\\$6000\\). Interest = 5% of 6000 = \\(\\$300\\).<br>Total in bank = 6000 + 300 = \\(\\$6300\\). Answer: \\(\\$6300\\).",
    "answers": [
      "6300",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14844,
    "id": 26075,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "East is directly to the right on the grid (N arrow points up).<br>Point H is on the same row as F, to the right, so H is east of F.<br>Answer: H.",
    "answers": [
      "H",
      "E",
      "G",
      "D"
    ],
    "correct_index": 0
  },
  {
    "index": 14845,
    "id": 26076,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "South-west means down-and-left.<br>B is down-and-left of G (G is up-and-right of B), so B is south-west of G.<br>Answer: G.",
    "answers": [
      "G",
      "A",
      "C",
      "E"
    ],
    "correct_index": 0
  },
  {
    "index": 14846,
    "id": 26077,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "7 units = 840 ml, so 1 unit = 120 ml.<br>Blue = 3 units = 3 × 120 = 360 ml.<br>Answer: 360 ml.",
    "answers": [
      "360",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14847,
    "id": 26078,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "2.00 to 4.15 p.m.<br>= 2 h 15 min.<br>First hour = \\(\\$6.00\\). Remaining 1 h 15 min = three half-hour blocks (0.5+0.5+0.25 rounded up) = 3 × \\(\\$2.50\\",
    "answers": [
      "27",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14848,
    "id": 26079,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "QR is parallel to PS.<br>In triangle RUS, ∠RUS = 180° - 47° - 80° = 53°.<br>∠QRU = ∠RUS = 53° (alternate angles, QR // PS...<br>).<br>Printed answer: ",
    "answers": [
      "53",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14849,
    "id": 26080,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "4 units = 24 cm², so 1 unit = 6 cm².<br>Rectangle = 15 units = 90 cm².<br>Shaded part = rectangle - unshaded triangle = 11 units = 11 × 6 = 66 cm².<br",
    "answers": [
      "66",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14850,
    "id": 26081,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total buttons = 80 + 130 = 210.<br>Red percentage = \\(\\dfrac{80}{210} \\times 100\\%\\) = 38.0952...% ≈ 38.10%.<br>Answer: 38.10%.",
    "answers": [
      "38.10",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14851,
    "id": 26082,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Printer A = 80 copies/min.<br>Printer B = 300 ÷ 5 = 60 copies/min.<br>80 > 60, so Printer A is faster.<br>Answer: Printer A.",
    "answers": [
      "Printer A",
      "Printer B",
      "Both print at the same rate",
      "Cannot be determined"
    ],
    "correct_index": 0
  },
  {
    "index": 14852,
    "id": 26083,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Printer A = 80/min, Printer B = 60/min.<br>Difference = 80 - 60 = 20 copies.<br>Answer: 20 copies.",
    "answers": [
      "20",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14853,
    "id": 26084,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Each round trip = \\(5\\dfrac{4}{5} \\times 2 = 11\\dfrac{3}{5}\\) km.<br>Over 7 days: \\(5\\dfrac{4}{5} \\times 7 \\times 2 = \\dfrac{29}{5} \\times 14 = \\dfrac",
    "answers": [
      "\\(81\\dfrac{1}{5}\\) km",
      "\\(40\\dfrac{3}{5}\\) km",
      "\\(11\\dfrac{3}{5}\\) km",
      "\\(81\\dfrac{4}{5}\\) km"
    ],
    "correct_index": 0
  },
  {
    "index": 14854,
    "id": 26085,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "1.3 kg = 1300 g = 13 lots of 100 g.<br>Cost = 13 × \\(\\$0.80\\) = \\(\\$10.40\\).<br>Answer: \\(\\$10.40\\).",
    "answers": [
      "10.40",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14855,
    "id": 26086,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "4 bowls cost 4 × \\(\\$2\\) = \\(\\$8\\) more than 4 mugs.<br>Remove that: \\(\\$53\\) - \\(\\$8\\) = \\(\\$45\\) for 9 items at the mug price. 1 mug = \\(\\$45\\) ÷ 9 ",
    "answers": [
      "25",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14856,
    "id": 26087,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Total sold = 120.<br>75% of 120 = 90 buns, reached at 14 00.<br>(b) The steepest rise is between 12 00 and 13 00, where 40 buns were sold.<br>Answ",
    "answers": [
      "1400",
      "1200",
      "1300",
      "40"
    ],
    "correct_index": null
  },
  {
    "index": 14857,
    "id": 26088,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "From the graph: Jan = \\(\\$45\\), Feb = \\(\\$25\\), Mar = \\(\\$0\\), Apr = \\(\\$65\\).<br>Total Jan-Apr = 45 + 25 + 0 + 65 = \\(\\$135\\). Average = \\(\\$135\\) ÷ ",
    "answers": [
      "33.75",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14858,
    "id": 26089,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) Full volume = 40 × 30 × 50 = 60000 cm³.<br>Syrup = 1/5 × 60000 = 12000 cm³ = 12 ℓ.<br>(b) Volume up to 45 cm = 45 × 40 × 30 = 54000 cm³.<br>Water ",
    "answers": [
      "12",
      "28",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14859,
    "id": 26090,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Take morning total as 14 units.<br>Given to neighbours = 4 units (2/7 of 14).<br>Remaining = 10 units; given to friends = 5 units (half).<br>Total giv",
    "answers": [
      "\\(\\dfrac{9}{14}\\)",
      "\\(\\dfrac{5}{14}\\)",
      "\\(\\dfrac{5}{7}\\)",
      "\\(\\dfrac{2}{7}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14860,
    "id": 26091,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "She gave away 9/14 in the morning, keeping 5/14.<br>End amount = morning + 13, and end = kept + 85.<br>So (5/14)m + 85 = m + 13 → 85 - 13 = m - (5/14)",
    "answers": [
      "197",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14861,
    "id": 26092,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "30 batteries = 60 nail-masses.<br>Difference: (box + 60 nails) - (box + 40 nails) = 1.08 kg - 0.78 kg = 0.30 kg = 20 nail-masses.<br>So 1 nail = 0.015",
    "answers": [
      "0.18",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14862,
    "id": 26093,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) In the end all equal: 540 ÷ 3 = 180 each.<br>(b) Working back: Adam ended with 180 after giving 1/4 away, so 3/4 of Adam's start = 180 → Adam star",
    "answers": [
      "180",
      "210",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14863,
    "id": 26094,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Difference in bows = 30 - 10 = 20 bows, using 8.5 - 1.5 = 7 m.<br>So each bow uses 7 ÷ 20 = 0.35 m.<br>Total ribbon = 30×0.35 + 1.5 = 12 m.<br>Max bow",
    "answers": [
      "34",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14864,
    "id": 26095,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total for figure n = n², so Figure 6 total = 36.<br>The white/grey counts repeat in pairs: Figure 6 white = 15, grey = 21 (15 + 21 = 36).<br>Answers: ",
    "answers": [
      "15",
      "21",
      "36",
      null
    ],
    "correct_index": null
  },
  {
    "index": 14865,
    "id": 26096,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total in figure n = n², so Figure 50 = 50 × 50 = 2500.<br>Answer: 2500.",
    "answers": [
      "2500",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14866,
    "id": 26097,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Total in Figure 50 = 2500.<br>Grey - white = 50 (the figure number).<br>Grey + white = 2500.<br>Grey = (2500 + 50) ÷ 2 = 1275.<br>Fraction grey = \\(\\d",
    "answers": [
      "\\(\\dfrac{51}{100}\\)",
      "\\(\\dfrac{49}{100}\\)",
      "\\(\\dfrac{1}{2}\\)",
      "\\(\\dfrac{50}{100}\\)"
    ],
    "correct_index": 0
  },
  {
    "index": 14867,
    "id": 26098,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Each angle of an equilateral triangle is 60°.<br>At the fold, the angle on the straight line = 180° - 60° - 53° = 67°.<br>The folded flap is congruent",
    "answers": [
      "46",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14868,
    "id": 26099,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Square side = 34 cm, so square perimeter = 136 cm.<br>Rectangle perimeter = 136 - 72 = 64 cm.<br>With one pair of sides = 10 cm each: 2×10 + 2×FE = 64",
    "answers": [
      "22",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14869,
    "id": 26100,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "Area of square = 34×34 = 1156 cm²; rectangle = 22×10 = 220 cm².<br>Unshaded triangles: ΔEFG = 0.5×22×10 = 110; ΔABG = 0.5×12×34 = 204; ΔBCE = 0.5×44×3",
    "answers": [
      "314",
      null,
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14870,
    "id": 26101,
    "type": 2,
    "flags": [
      "OK"
    ],
    "solution_preview": "(a) In rhombus ABCD, ∠ABC = 180° - 56° = 124° (co-interior).<br>Angles at B around the point: ∠ABE = 360° - 140° - 124° = 96°.<br>(b) Diagonal BD bise",
    "answers": [
      "96",
      "22",
      null,
      null
    ],
    "correct_index": null
  },
  {
    "index": 14871,
    "id": 26102,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Work brackets first, then division, then subtraction.<br>\\((6+12)=18\\); \\(18\\div3=6\\); \\(33-6=27\\).",
    "answers": [
      "5",
      "13",
      "27",
      "31"
    ],
    "correct_index": 2
  },
  {
    "index": 14872,
    "id": 26103,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "In 10 245 the digit 2 is in the hundreds place, so its value is \\(2 \\times 100 = 200\\).",
    "answers": [
      "20",
      "200",
      "2000",
      "20 000"
    ],
    "correct_index": 1
  },
  {
    "index": 14873,
    "id": 26104,
    "type": 1,
    "flags": [
      "OK"
    ],
    "solution_preview": "Between 5.0 and the next mark each interval is 0.02 (the major marks 4.8, 4.9, 5.0 are split into 5 small parts of 0.02).<br>M is 3 small marks past 5",
    "answers": [
      "5.3",
      "5.6",
      "5.03",
      "5.06"
    ],
    "correct_index": 3
  }
]