{
  "paper": {
    "school": "Nan Hua",
    "year": 2024,
    "level": "P5",
    "label": "Weighted Assessment 2",
    "source_prefix": "Nan Hua 2024 P5 Weighted Assessment 2",
    "has_answer_key": true
  },
  "questions": [
    {
      "n": 1,
      "type_id": 1,
      "question": "In the triangle DEG, which base is related to the height EF?",
      "answer0": "DF",
      "answer1": "DG",
      "answer2": "GE",
      "answer3": "GF",
      "correct_answer": 1,
      "skill_id": 185,
      "difficulty_id": 2,
      "explanation": "The height EF is drawn perpendicular from vertex E. The base must be the side perpendicular to this height. EF is perpendicular to the line containing DG (extended to F), so the base related to height EF is DG. Answer: DG.",
      "hints": ["The base and its corresponding height are always perpendicular to each other.", "EF is dropped from vertex E; find the side it meets at a right angle."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q1",
      "image_needed": true,
      "image_options": false,
      "image_file": "q1.png",
      "image_page": 3,
      "image_bbox": [0.18, 0.25, 0.55, 0.40],
      "image_loc": "triangle DEG with dashed height EF, upper-left below the question text",
      "notes": "Answer key: option 2 (DG)."
    },
    {
      "n": 2,
      "type_id": 1,
      "question": "ACDE is a rectangle. Find the area of the shaded triangle EBD.",
      "answer0": "15 cm²",
      "answer1": "20 cm²",
      "answer2": "30 cm²",
      "answer3": "60 cm²",
      "correct_answer": 2,
      "skill_id": 186,
      "difficulty_id": 2,
      "explanation": "Triangle EBD has base ED = 10 cm and height = 6 cm (the height of the rectangle). Area = \\(\\dfrac{1}{2} \\times 10 \\times 6 = 30\\) cm². Answer: 30 cm².",
      "hints": ["Base of the triangle is ED = 10 cm; its height is the rectangle's height 6 cm.", "Area of triangle = \\(\\dfrac{1}{2} \\times \\text{base} \\times \\text{height}\\)."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q2",
      "image_needed": true,
      "image_options": false,
      "image_file": "q2.png",
      "image_page": 3,
      "image_bbox": [0.33, 0.57, 0.70, 0.73],
      "image_loc": "rectangle ACDE with shaded triangle EBD, labelled 6 cm (height) and 10 cm (base)",
      "notes": "Answer key: option 3 (30 cm²)."
    },
    {
      "n": 3,
      "type_id": 1,
      "question": "What is the ratio of the length of eraser to the length of pencil to the length of crayon?",
      "answer0": "3 : 6 : 11",
      "answer1": "3 : 11 : 6",
      "answer2": "4 : 7 : 11",
      "answer3": "4 : 11 : 7",
      "correct_answer": 1,
      "skill_id": 180,
      "difficulty_id": 2,
      "explanation": "Reading the ruler: eraser = 3 cm, pencil = 11 cm, crayon = 6 cm. So eraser : pencil : crayon = 3 : 11 : 6. Answer: 3 : 11 : 6.",
      "hints": ["Read each object's length off the centimetre ruler from its start to its end.", "Keep the order eraser : pencil : crayon as asked."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q3",
      "image_needed": true,
      "image_options": false,
      "image_file": "q3.png",
      "image_page": 4,
      "image_bbox": [0.17, 0.13, 0.85, 0.30],
      "image_loc": "crayon, pencil and eraser laid over a centimetre ruler, top of page",
      "notes": "Answer key: option 2 (3 : 11 : 6). Eraser 3 cm, pencil 11 cm, crayon 6 cm."
    },
    {
      "n": 4,
      "type_id": 1,
      "question": "Ali bought 36 chocolates and 64 sweets. Find the ratio of the number of chocolates to the total number of sweets and chocolates bought by Ali.",
      "answer0": "9 : 16",
      "answer1": "9 : 25",
      "answer2": "16 : 9",
      "answer3": "25 : 9",
      "correct_answer": 1,
      "skill_id": 179,
      "difficulty_id": 2,
      "explanation": "Total = 36 + 64 = 100. Chocolates : total = 36 : 100. Divide both by 4: 9 : 25. Answer: 9 : 25.",
      "hints": ["Total number of items = 36 + 64.", "Write chocolates : total, then simplify by dividing by the common factor."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q4",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Answer key: option 2 (9 : 25)."
    },
    {
      "n": 5,
      "type_id": 1,
      "question": "Ava, Betty and Charles have $77 altogether. The ratio of Ava's money to Betty's money to Charles' money is 1 : 4 : 6. How much money do Ava and Charles have altogether?",
      "answer0": "$7",
      "answer1": "$28",
      "answer2": "$35",
      "answer3": "$49",
      "correct_answer": 3,
      "skill_id": 183,
      "difficulty_id": 2,
      "explanation": "Total units = 1 + 4 + 6 = 11. 1 unit = $77 ÷ 11 = $7. Ava and Charles = 1 + 6 = 7 units = 7 × $7 = $49. Answer: $49.",
      "hints": ["Add the ratio parts to get the total number of units.", "Find the value of 1 unit, then add Ava's and Charles' units."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q5",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Answer key: option 4 ($49)."
    },
    {
      "n": 6,
      "type_id": 2,
      "question": "Find the missing number in the box.<br>\\(6 : 9 = 14 : \\) [?]",
      "answer0": "21",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 181,
      "difficulty_id": 1,
      "explanation": "6 : 9 simplifies to 2 : 3. 14 is 7 × 2, so the missing term is 7 × 3 = 21. Check: 14 : 21 = 2 : 3. Answer: 21.",
      "hints": ["Simplify 6 : 9 to its simplest form first.", "Find what 6 was multiplied by to get 14, then apply it to 9."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q6",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Answer key: 21."
    },
    {
      "n": 7,
      "type_id": 2,
      "question": "The following solid is made up of 1-cm cubes. What is the volume of the solid? [?]",
      "answer0": "18",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 190,
      "difficulty_id": 1,
      "explanation": "Count the unit cubes making up the solid: there are 18 cubes. Each cube is 1 cm³, so the volume = 18 cm³. Answer: 18 cm³.",
      "hints": ["Each small cube is 1 cm³.", "Count all the cubes, including those at the back and in the lower layer."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q7",
      "image_needed": true,
      "image_options": false,
      "image_file": "q7.png",
      "image_page": 6,
      "image_bbox": [0.20, 0.52, 0.55, 0.78],
      "image_loc": "L-shaped/staircase solid built from 1-cm cubes, lower-left of page",
      "notes": "Answer key: 18 cm³. Unit is cm³ (answer printed without unit field). Count verified against key = 18 cubes."
    },
    {
      "n": 8,
      "type_id": 0,
      "question": "Draw cuboid A on the isometric grid provided.",
      "answer0": null,
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 189,
      "difficulty_id": 2,
      "explanation": "Draw a cuboid measuring 3 units by 3 units (base) by 2 units (height) on the isometric dot grid, matching Cuboid A.",
      "hints": [],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q8",
      "image_needed": true,
      "image_options": false,
      "image_file": "q8.png",
      "image_page": 7,
      "image_bbox": [0.12, 0.18, 0.45, 0.40],
      "image_loc": "Cuboid A (3 units x 3 units x 2 units) on the left, with isometric dot grid on the right",
      "notes": "Drawing/construction task — no value answer; type_id 0, skipped on insert. Answer key shows a 3x3x2 cuboid drawn on the isometric grid."
    },
    {
      "n": 9,
      "type_id": 0,
      "question": "The solid is made up of 9 cubes. Draw the top view of the solid on the grid provided.",
      "answer0": null,
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 188,
      "difficulty_id": 2,
      "explanation": "Looking down from above, the top view is an L-shaped outline of squares matching the footprint plus the raised cubes, as shown in the answer key.",
      "hints": [],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q9",
      "image_needed": true,
      "image_options": false,
      "image_file": "q9.png",
      "image_page": 7,
      "image_bbox": [0.18, 0.55, 0.45, 0.74],
      "image_loc": "isometric solid of 9 cubes with Top/Front/Side view arrows, lower-left of page",
      "notes": "Draw-the-view task — no value answer; type_id 0, skipped on insert. Answer key shows the L-shaped top-view drawn on the dot grid."
    },
    {
      "n": 10,
      "type_id": 1,
      "question": "David is 12 years old. Elly is 9 years old. Find the ratio of David's age to Elly's age in 3 years' time.",
      "answer0": "5 : 4",
      "answer1": "4 : 5",
      "answer2": "4 : 3",
      "answer3": "12 : 9",
      "correct_answer": 0,
      "skill_id": 179,
      "difficulty_id": 2,
      "explanation": "In 3 years' time: David = 12 + 3 = 15, Elly = 9 + 3 = 12. Ratio David : Elly = 15 : 12 = 5 : 4. Answer: 5 : 4.",
      "hints": ["Add 3 years to each person's age first.", "Then write the ratio and simplify by dividing by the common factor."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q10",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Answer key: 15 + 3 = ... gives David 15, Elly 12, ratio 15:12 = 5:4. Converted to MCQ because answer is a ratio (not FIB). Distractors include unsimplified and reversed forms."
    },
    {
      "n": 11,
      "type_id": 2,
      "question": "ABDE is a square and BCD is a triangle. Find the area of triangle BCD. [?]",
      "answer0": "24",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 186,
      "difficulty_id": 2,
      "explanation": "Triangle BCD has base BC = 6 cm and height BD = 8 cm (BD is the side of the square, equal to ED = 8 cm), with the right angle at B. Area = \\(\\dfrac{1}{2} \\times 8 \\times 6 = 24\\) cm². Answer: 24 cm².",
      "hints": ["BD is a side of the square ABDE, so BD = 8 cm.", "Use the right angle at B: area = \\(\\dfrac{1}{2} \\times BC \\times BD\\)."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q11",
      "image_needed": true,
      "image_options": false,
      "image_file": "q11.png",
      "image_page": 8,
      "image_bbox": [0.28, 0.46, 0.62, 0.68],
      "image_loc": "square ABDE with attached triangle BCD; BC = 6 cm, slant 10 cm, ED = 8 cm",
      "notes": "Answer key: 1/2 x 8 x 6 = 24 cm². Unit cm². FIB answer is whole number 24."
    },
    {
      "n": 12,
      "type_id": 2,
      "question": "ABDE is a square. BC = CD. The area of ACD is 15 cm². What is the area of the square? [?]",
      "answer0": "60",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 186,
      "difficulty_id": 3,
      "explanation": "Triangle ACD has area 15 cm². Since BC = CD, C is the midpoint of BD, so triangle ACD is half of triangle ABD. Triangle ABD is half of the square. The answer key works it as 15 × 4 = 60 cm². Answer: 60 cm².",
      "hints": ["BC = CD means C is the midpoint of side BD.", "Relate triangle ACD to triangle ABD, and triangle ABD to the whole square."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 1 Q12",
      "image_needed": true,
      "image_options": false,
      "image_file": "q12.png",
      "image_page": 9,
      "image_bbox": [0.30, 0.22, 0.60, 0.42],
      "image_loc": "square ABDE with diagonal AD and point C on BD (BC = CD), shaded triangle ACD",
      "notes": "Answer key: 15 x 4 = 60 cm². FIB answer whole number 60."
    },
    {
      "n": 13,
      "type_id": 2,
      "question": "The box is filled with some 1-cm cubes.<br>(a) What is the volume of the box? [?]<br>(b) How many more 1-cm cubes are needed to fill up the box completely? [?]",
      "answer0": "165",
      "answer1": "148",
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 193,
      "difficulty_id": 2,
      "explanation": "(a) The box dimensions are 3 cm by 5 cm by 11 cm, so volume = 3 × 5 × 11 = 165 cm³. (b) There are already 17 cubes inside, so cubes still needed = 165 − 17 = 148. Answers: (a) 165 cm³, (b) 148.",
      "hints": ["Volume of a cuboid = length × breadth × height.", "Count the cubes already placed, then subtract from the total volume."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 2 Q1",
      "image_needed": true,
      "image_options": false,
      "image_file": "q13.png",
      "image_page": 11,
      "image_bbox": [0.18, 0.16, 0.85, 0.37],
      "image_loc": "open cuboid box partly filled with 1-cm cubes along one edge, top of page",
      "notes": "Answer key: (a) 3 x 5 x 11 = 165 cm³; (b) 165 - 17 = 148. Part (a) unit cm³. Both FIB answers whole numbers."
    },
    {
      "n": 14,
      "type_id": 2,
      "question": "ACEF is a rectangle. BC = CD. Find the area of the shaded part. [?]",
      "answer0": "156",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 186,
      "difficulty_id": 3,
      "explanation": "Rectangle ACEF: AF = 14 cm, FE = 25 cm. The shaded region = triangle FBC (or whole) minus the unshaded triangles. Answer key working: \\(\\dfrac{1}{2} \\times 6 \\times 25 = 75\\); \\(\\dfrac{1}{2} \\times 14 \\times 17 = 119\\); rectangle 14 × 25 = 350; shaded = 350 − 119 − 75 = 156 cm². Answer: 156 cm².",
      "hints": ["Find the area of the whole rectangle first (14 × 25).", "Subtract the two unshaded triangles to leave the shaded part."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 2 Q2",
      "image_needed": true,
      "image_options": false,
      "image_file": "q14.png",
      "image_page": 12,
      "image_bbox": [0.27, 0.15, 0.74, 0.35],
      "image_loc": "rectangle ACEF with shaded quadrilateral/triangle from F; 14 cm, 25 cm, 6 cm marked",
      "notes": "Answer key: 1/2 x 6 x 25 = 75; 1/2 x 14 x 17 = 119; 14 x 25 = 350; 350 - 119 - 75 = 156 cm². FIB answer whole number 156, unit cm²."
    },
    {
      "n": 15,
      "type_id": 0,
      "question": "Alice, Peter and John have some pens. The ratio of the number of Alice's pens to the number of Peter's pens to the number of John's pens is 1 : 2 : 5. Each of the statements is either true, false or not possible to tell from the information given. (a) Alice has twice as many pens as Peter. (b) If John has 40 pens, Alice and Peter will have 24 pens altogether. (c) They have 56 pens altogether.",
      "answer0": null,
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 177,
      "difficulty_id": 2,
      "explanation": "(a) FALSE — the ratio 1 : 2 means Peter has twice as many as Alice, not the reverse. (b) TRUE — if John = 5 units = 40, then 1 unit = 8, so Alice + Peter = 3 units = 24. (c) NOT POSSIBLE TO TELL — the total depends on the unit value, which is not given. Answers: (a) False, (b) True, (c) Not possible to tell.",
      "hints": [],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 2 Q3",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "True/False/Not-possible tick-table — interactive format, no single value/sequence answer; type_id 0, skipped on insert. Answer key: (a) False, (b) True, (c) Not possible to tell."
    },
    {
      "n": 16,
      "type_id": 2,
      "question": "ABCD is a square with sides 22 cm and DE = EC. Figure AFBED has a total area of 198 cm², find the area of the shaded triangle DEF. [?]",
      "answer0": "44",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 186,
      "difficulty_id": 3,
      "explanation": "Triangle ABD (half the square) has area \\(\\dfrac{1}{2} \\times 22 \\times 22 = 242\\) cm². Wait — using the answer key: \\(\\dfrac{1}{2} \\times 11 \\times 22 = 121\\), then 121 × 2 = 242, and shaded DEF = 242 − 198 = 44 cm². Answer: 44 cm².",
      "hints": ["E is the midpoint of DC since DE = EC; the side is 22 cm.", "Find the relevant triangle area, then subtract the given figure area 198 cm²."],
      "source": "Nan Hua 2024 P5 Weighted Assessment 2 Paper 2 Q4",
      "image_needed": true,
      "image_options": false,
      "image_file": "q16.png",
      "image_page": 14,
      "image_bbox": [0.30, 0.15, 0.66, 0.40],
      "image_loc": "square ABCD with lines from A and B meeting at F above E (midpoint of DC); shaded triangle DEF; side 22 cm marked",
      "notes": "Answer key: 1/2 x 11 x 22 = 121; 121 x 2 = 242; 242 - 198 = 44 cm². FIB answer whole number 44, unit cm²."
    }
  ]
}