{
"paper": {
"school": "CHIJ St Nicholas Girls' School (Primary)",
"year": 2022,
"level": "P5",
"label": "Weighted Assessment 2",
"source_prefix": "CHIJ 2022 P5 Weighted Assessment 2",
"has_answer_key": true
},
"questions": [
{
"n": 1,
"type_id": 2,
"question": "A shop sells pens. One pen costs $2 and 1 packet of 4 pens costs $5. Benny wants to buy 101 pens. What is the least amount of money Benny needs to buy the 101 pens? Ans: $[?]",
"answer0": "127",
"answer1": null,
"answer2": null,
"answer3": null,
"correct_answer": null,
"skill_id": 152,
"difficulty_id": 2,
"explanation": "Buying by the packet ($5 for 4 pens = $1.25/pen) is cheaper than $2 each, so buy as many full packets as possible. 101 = 25 packets (100 pens) with 1 pen left over. 25 packets x $5 = $125. The last single pen costs $2. Total = $125 + $2 = $127.",
"hints": [
"A packet of 4 pens for $5 is cheaper per pen than $2 each, so buy whole packets first.",
"101 pens = 25 full packets (100 pens) + 1 single pen. Cost = 25 x $5 + 1 x $2."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q1",
"image_needed": true,
"image_options": false,
"image_file": "q1.png",
"image_page": 2,
"image_bbox": [0.27, 0.20, 0.70, 0.34],
"notes": "Figure shows one pen labelled '$2 for each pen' and a packet of 4 pens labelled '1 packet for $5'. The packet count (4 pens) is needed and is stated in the stem."
},
{
"n": 2,
"type_id": 2,
"question": "ABC is a triangle. AD is perpendicular to DC. DB = 9 cm, BC = 7 cm, AD = 12 cm, AB = 15 cm and AC = 20 cm. What is the area of the triangle ABC? Ans: [?] cm²",
"answer0": "42",
"answer1": null,
"answer2": null,
"answer3": null,
"correct_answer": null,
"skill_id": 186,
"difficulty_id": 2,
"explanation": "Take BC as the base (7 cm) and AD as the corresponding height (12 cm), since AD is perpendicular to the line DBC. Area of triangle = \\(\\dfrac{1}{2}\\) x base x height = \\(\\dfrac{1}{2}\\) x 7 x 12 = 42 cm².",
"hints": [
"Area of a triangle = \\(\\dfrac{1}{2}\\) x base x height.",
"Use base BC = 7 cm with the perpendicular height AD = 12 cm."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q2",
"image_needed": true,
"image_options": false,
"image_file": "q2.png",
"image_page": 3,
"image_bbox": [0.18, 0.10, 0.62, 0.30],
"notes": "Figure: triangle with apex A, foot D (right angle), then B and C along the base line. AD=12, DB=9, BC=7, AB=15, AC=20. Key uses base 7 x height 12."
},
{
"n": 3,
"type_id": 1,
"question": "The figure is made up of identical rectangles. What is the ratio of the number of shaded rectangles to the number of unshaded rectangles to the total number of rectangles? Express the answer in its simplest form.",
"answer0": "1 : 3 : 4",
"answer1": "4 : 12 : 16",
"answer2": "1 : 4 : 5",
"answer3": "1 : 3 : 5",
"correct_answer": 0,
"skill_id": 179,
"difficulty_id": 2,
"explanation": "The 4 x 4 grid has 16 rectangles in total. 4 of them are shaded, so 16 - 4 = 12 are unshaded. The ratio shaded : unshaded : total = 4 : 12 : 16. Dividing each term by 4 gives 1 : 3 : 4.",
"hints": [
"Count the shaded rectangles, the unshaded rectangles, and the total (shaded + unshaded).",
"Divide all three terms by their highest common factor to simplify the ratio."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q3",
"image_needed": true,
"image_options": false,
"image_file": "q3.png",
"image_page": 3,
"image_bbox": [0.34, 0.52, 0.62, 0.66],
"notes": "Figure: a 4-column x 4-row grid of identical rectangles with 4 shaded. Counts: shaded 4, unshaded 12, total 16 (key). Ratio answer => MCQ."
},
{
"n": 4,
"type_id": 1,
"question": "Mrs Sanvi bought 15 m of cloth. She used \\(\\dfrac{1}{3}\\) of it to make a dress and \\(1\\dfrac{1}{2}\\) m to make curtains. How much cloth did she have left?",
"answer0": "\\(8\\dfrac{1}{2}\\) m",
"answer1": "\\(9\\dfrac{1}{2}\\) m",
"answer2": "10 m",
"answer3": "\\(13\\dfrac{1}{2}\\) m",
"correct_answer": 0,
"skill_id": 165,
"difficulty_id": 2,
"explanation": "Cloth used for the dress = \\(\\dfrac{1}{3}\\) x 15 = 5 m. After the dress: 15 - 5 = 10 m. After the curtains: 10 - \\(1\\dfrac{1}{2}\\) = \\(8\\dfrac{1}{2}\\) m. She had \\(8\\dfrac{1}{2}\\) m left.",
"hints": [
"First find \\(\\dfrac{1}{3}\\) of 15 m for the dress.",
"Subtract the dress cloth, then subtract the \\(1\\dfrac{1}{2}\\) m of curtains from what is left."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q4",
"image_needed": false,
"image_options": false,
"image_file": null,
"image_page": null,
"image_bbox": null,
"notes": "Answer is the mixed number 8 1/2 m => MCQ (FIB is integer/decimal only)."
},
{
"n": 5,
"type_id": 2,
"question": "During a sports carnival, Alex, Ben and Chaga ran a total distance of 5.6 km. Alex ran 0.8 km more than Ben. Chaga ran twice the distance that Ben ran. How far did Alex run? Express the answer in kilometres. Ans: [?] km",
"answer0": "2",
"answer1": null,
"answer2": null,
"answer3": null,
"correct_answer": null,
"skill_id": 167,
"difficulty_id": 2,
"explanation": "Let Ben = 1 unit. Alex = 1 unit + 0.8 km, Chaga = 2 units. Total = 4 units + 0.8 = 5.6 km, so 4 units = 5.6 - 0.8 = 4.8 km and 1 unit = 4.8 / 4 = 1.2 km (Ben). Alex = 1.2 + 0.8 = 2 km.",
"hints": [
"Let Ben's distance be 1 unit; write Alex and Chaga in terms of units and the 0.8 km.",
"Subtract the extra 0.8 km from the total before dividing to find 1 unit (Ben), then add 0.8 km for Alex."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q5",
"image_needed": false,
"image_options": false,
"image_file": null,
"image_page": null,
"image_bbox": null,
"notes": "Answer 2 km (a whole number / decimal) => FIB valid."
},
{
"n": 6,
"type_id": 1,
"question": "At first, Mindy had 250 beads and Siti had 100 beads. Mindy gave Siti 20 beads. What was the ratio of the number of beads that Mindy had to the number of beads that Siti had in the end? Express the answer in its simplest form.",
"answer0": "23 : 12",
"answer1": "25 : 10",
"answer2": "5 : 2",
"answer3": "23 : 14",
"correct_answer": 0,
"skill_id": 179,
"difficulty_id": 2,
"explanation": "After giving away 20 beads, Mindy had 250 - 20 = 230 beads. Siti had 100 + 20 = 120 beads. Ratio Mindy : Siti = 230 : 120. Dividing both terms by 10 gives 23 : 12.",
"hints": [
"Work out how many beads each girl has AFTER Mindy gives 20 to Siti.",
"Write Mindy : Siti and divide both numbers by their common factor."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q6",
"image_needed": false,
"image_options": false,
"image_file": null,
"image_page": null,
"image_bbox": null,
"notes": "Ratio answer 23:12 => MCQ."
},
{
"n": 7,
"type_id": 2,
"question": "The figure shows a rectangle. ∠b = ∠c. What is the sum of ∠a, ∠b and ∠c? Ans: [?]°",
"answer0": "186",
"answer1": null,
"answer2": null,
"answer3": null,
"correct_answer": null,
"skill_id": 230,
"difficulty_id": 2,
"explanation": "The two lines from the top corners meet at the top edge, and ∠a is the angle at the top-left corner of the rectangle = 90°. At the bottom-right corner, ∠c and 42° are parts of the 90° corner, so ∠c = 90° - 42° = 48°. Since ∠b = ∠c, ∠b = 48°. Sum = 90° + 48° + 48° = 186°.",
"hints": [
"Each corner of a rectangle is 90°; use the 42° to find ∠c first.",
"∠c = 90° - 42°, and ∠b = ∠c. Then add ∠a (= 90°) + ∠b + ∠c."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q7",
"image_needed": true,
"image_options": false,
"image_file": "q7.png",
"image_page": 7,
"image_bbox": [0.22, 0.13, 0.66, 0.28],
"notes": "Figure: rectangle with two lines drawn from the top corners meeting at the top edge; angle a at top-left, angle b at bottom-left, angle c plus 42 degrees at bottom-right. Key answer 186 degrees."
},
{
"n": 8,
"type_id": 1,
"question": "Every morning, Ismail takes the MRT and bus to go to school. The MRT journey takes 40 min and the bus journey takes 25 min.
(a) How long does he take to travel to school every morning altogether? Express the answer in hour and minutes.
(b) One day, when Ismail reached school, his watch showed 7.15 a.m. His watch was 10 min fast that day. What was the actual time when he left home that day?",
"answer0": "(a) 1 h 5 min (b) 6.00 a.m.",
"answer1": "(a) 1 h 5 min (b) 6.10 a.m.",
"answer2": "(a) 1 h 15 min (b) 6.00 a.m.",
"answer3": "(a) 65 min (b) 5.50 a.m.",
"correct_answer": 0,
"skill_id": 93,
"difficulty_id": 2,
"explanation": "(a) Total travel time = 40 min + 25 min = 65 min = 1 h 5 min. (b) The watch was 10 min fast, so the actual arrival time was 7.15 a.m. - 10 min = 7.05 a.m. Subtract the 1 h 5 min travel time: 7.05 a.m. - 1 h 5 min = 6.00 a.m.",
"hints": [
"(a) Add the two journey times, then convert 65 min into hours and minutes.",
"(b) First correct the watch (it is 10 min fast) to get the real arrival time, then subtract the total travel time."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q8",
"image_needed": false,
"image_options": false,
"image_file": null,
"image_page": null,
"image_bbox": null,
"notes": "Two-part time question; answers '1 h 5 min' (compound time) and '6.00 a.m.' (clock time) are non-numeric => MCQ with combined options. Key: (a) 1 h 5 min, (b) 6.00 a.m."
},
{
"n": 9,
"type_id": 2,
"question": "Figure 1 is made up of 2 squares A and D and 2 rectangles B and C. The total perimeter of B and C is 64 cm. The area of D is 81 cm². Figure 2 is made up of 3 identical square A.
(a) What is the area of square A? Ans: [?] cm²
(b) What is the perimeter of Figure 2? Ans: [?] cm",
"answer0": "49",
"answer1": "56",
"answer2": null,
"answer3": null,
"correct_answer": null,
"skill_id": 138,
"difficulty_id": 3,
"explanation": "(a) Area of D = 81 cm², so the side of square D = 9 cm. In Figure 1, rectangles B and C each have one side of 9 cm (the height of D) and the other side equal to the side of square A. Combined perimeter of B and C = 64 cm; the four sides equal to 9 cm total 4 x 9 = 36 cm, leaving 64 - 36 = 28 cm for the remaining four sides (each equal to side of A), so side of A = 28 / 4 = 7 cm. Area of A = 7 x 7 = 49 cm². (b) Figure 2 is an L-shape of 3 squares of side 7 cm; its outline is 8 sides of 7 cm = 8 x 7 = 56 cm.",
"hints": [
"(a) Find the side of D from its area (81 = 9 x 9), then use the combined perimeter of B and C (64 cm) to find the side of A.",
"(b) Trace the outline of the L-shaped Figure 2 made of 3 squares of side 7 cm — it has 8 edges."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q9",
"image_needed": true,
"image_options": false,
"image_file": "q9.png",
"image_page": 9,
"image_bbox": [0.18, 0.17, 0.78, 0.38],
"notes": "Two figures: Figure 1 = 2x2 arrangement of squares A (top-left), B (top-right), C (bottom-left), D (bottom-right); Figure 2 = L-shape of 3 squares labelled A. Both parts FIB integers. Key: (a) 49 cm2, (b) 56 cm."
},
{
"n": 10,
"type_id": 2,
"question": "Rahim spent \\(\\dfrac{2}{5}\\) of his money on 3 similar shirts and 5 similar dresses. A dress cost twice as much as a shirt. He spent \\(\\dfrac{1}{6}\\) of his remaining money on a bag and had $175.50 left.
(a) How much money did the bag cost? Ans: $[?]
(b) How much more money did the bag cost than one shirt? Ans: $[?]",
"answer0": "35.10",
"answer1": "24.30",
"answer2": null,
"answer3": null,
"correct_answer": null,
"skill_id": 175,
"difficulty_id": 3,
"explanation": "(a) After buying the clothes, \\(\\dfrac{3}{5}\\) of his money remained. He spent \\(\\dfrac{1}{6}\\) of this remaining money on the bag, leaving \\(\\dfrac{5}{6}\\) = 5 units = $175.50, so 1 unit = $175.50 / 5 = $35.10. The bag (1 unit) cost $35.10. (b) Bag = $35.10. The remaining \\(\\dfrac{3}{5}\\) money = 6 units = 6 x $35.10 = $210.60, so the clothes (\\(\\dfrac{2}{5}\\)) cost $210.60 / 3 x 2 = $140.40. Each dress = 2 shirts, so 3 shirts + 5 dresses = 3 + 10 = 13 shirt-units; 1 shirt = $140.40 / 13 = $10.80. Bag - shirt = $35.10 - $10.80 = $24.30.",
"hints": [
"(a) The bag was \\(\\dfrac{1}{6}\\) of the remaining money, so the $175.50 left is \\(\\dfrac{5}{6}\\) of that remainder — work back to 1 part (the bag).",
"(b) Express each dress as 2 shirts to count total shirt-units (3 + 5x2 = 13), find one shirt's cost, then subtract from the bag's cost."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q10",
"image_needed": false,
"image_options": false,
"image_file": null,
"image_page": null,
"image_bbox": null,
"notes": "Both parts money (decimal) => FIB valid. Key: (a) $35.10, (b) $24.30."
},
{
"n": 11,
"type_id": 2,
"question": "At first, Wonderlicious Bakery baked a total of 370 cupcakes, tarts and muffins. Half of its tarts and some muffins were sold. Then, 30 more cupcakes were baked. There was an equal number of cupcakes, tarts and muffins at the end. A total amount of $108 was collected from the sale of tarts. Each cupcake costs $2, each tart costs $1.50 and each muffin costs $4.
(a) How many tarts did Wonderlicious Bakery sell? Ans: [?]
(b) How much money was collected from the sale of muffins? Ans: $[?]",
"answer0": "72",
"answer1": "448",
"answer2": null,
"answer3": null,
"correct_answer": null,
"skill_id": 152,
"difficulty_id": 3,
"explanation": "(a) $108 was collected from tarts sold at $1.50 each, so tarts sold = 108 / 1.50 = 72. (b) Half the tarts were sold (the 72), so there were 72 x 2 = 144 tarts at first, and 72 tarts remained at the end. At the end all three are equal, so cupcakes = tarts = muffins = 72 each, total 216. Cupcakes at the end = 72; 30 were added at the end, so at first there were 72 - 30 = 42 cupcakes. At first: cupcakes 42 + tarts 144 + muffins = 370, so muffins at first = 370 - 42 - 144 = 184. Muffins at the end = 72, so muffins sold = 184 - 72 = 112. Money from muffins = 112 x $4 = $448.",
"hints": [
"(a) Tarts were sold at $1.50 each and raised $108 — divide to find how many tarts were sold.",
"(b) Half the tarts were sold, so find the starting number of tarts; use 'equal numbers at the end' (and the 30 extra cupcakes) to find starting muffins, then how many muffins were sold x $4."
],
"source": "CHIJ 2022 P5 Weighted Assessment 2 Q11",
"image_needed": false,
"image_options": false,
"image_file": null,
"image_page": null,
"image_bbox": null,
"notes": "Prices given in a table (Cupcake $2, Tart $1.50, Muffin $4) — inlined into the stem. Both parts numeric => FIB. Key: (a) 72 tarts, (b) $448."
}
]
}