{ "paper": { "school": "CHIJ St Nicholas Girls' School (Primary)", "year": 2022, "level": "P5", "label": "Semestral Assessment 2", "source_prefix": "CHIJ 2022 P5 Semestral Assessment 2", "has_answer_key": true }, "questions": [ { "n": 1, "type_id": 1, "question": "6 hundreds, 9 tens and 3 thousandths is [?]", "answer0": "690.3", "answer1": "690.003", "answer2": "609.3", "answer3": "609.003", "correct_answer": 1, "skill_id": 123, "difficulty_id": 1, "explanation": "6 hundreds = 600, 9 tens = 90, 3 thousandths = 0.003. Sum = 600 + 90 + 0.003 = 690.003.", "hints": ["Write each place value: hundreds, tens, thousandths.", "Thousandths is the 3rd decimal place."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q1", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 2 (690.003), 0-based index 1." }, { "n": 2, "type_id": 1, "question": "Find the difference between 85 812 and 23 167.
Round your answer to the nearest hundred.", "answer0": "62 000", "answer1": "62 600", "answer2": "62 700", "answer3": "63 000", "correct_answer": 1, "skill_id": 150, "difficulty_id": 1, "explanation": "85 812 - 23 167 = 62 645. Rounded to the nearest hundred = 62 600.", "hints": ["Subtract first, then round.", "Look at the tens digit (4) to round to the nearest hundred."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q2", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 2 (62 600), 0-based index 1." }, { "n": 3, "type_id": 1, "question": "\\(\\dfrac{3}{7}\\) of a number is 42. What is \\(\\dfrac{1}{2}\\) of this number?", "answer0": "18", "answer1": "21", "answer2": "49", "answer3": "98", "correct_answer": 2, "skill_id": 157, "difficulty_id": 2, "explanation": "\\(\\dfrac{3}{7}\\) of the number is 42, so \\(\\dfrac{1}{7}\\) = 42 ÷ 3 = 14. The whole number = 14 × 7 = 98. \\(\\dfrac{1}{2}\\) of 98 = 49.", "hints": ["Find 1/7 of the number first.", "Then find the whole, and halve it."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q3", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 3 (49), 0-based index 2." }, { "n": 4, "type_id": 1, "question": "Look at the number line. What is the value of X?", "answer0": "150", "answer1": "153", "answer2": "156", "answer3": "160", "correct_answer": 2, "skill_id": 108, "difficulty_id": 2, "explanation": "From 144 to 180 is 36, divided into 3 intervals of 12. X is one interval past 144: 144 + 12 = 156.", "hints": ["Find the value of each small interval.", "108 to 180 spans the marked range; count intervals to X."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q4", "image_needed": true, "image_options": false, "image_file": "q4.png", "image_page": 3, "image_bbox": [0.27, 0.41, 0.62, 0.50], "image_loc": "number line in the middle of the page, with 108, 144, 180 marked and X below an arrow", "notes": "Key: option 3 (156), 0-based index 2." }, { "n": 5, "type_id": 1, "question": "In an exhibition hall, there were 140 adults. 28 were women. What is the ratio of the number of men to the number of women?", "answer0": "1 : 4", "answer1": "1 : 5", "answer2": "4 : 1", "answer3": "5 : 1", "correct_answer": 2, "skill_id": 179, "difficulty_id": 2, "explanation": "Men = 140 - 28 = 112. Ratio men : women = 112 : 28 = 4 : 1.", "hints": ["Find the number of men first.", "Simplify the ratio by dividing both by 28."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q5", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 3 (4 : 1), 0-based index 2." }, { "n": 6, "type_id": 1, "question": "Express \\(\\dfrac{72}{120}\\) as a percentage.", "answer0": "0.06%", "answer1": "0.6%", "answer2": "6%", "answer3": "60%", "correct_answer": 3, "skill_id": 173, "difficulty_id": 1, "explanation": "\\(\\dfrac{72}{120}\\) × 100% = 60%.", "hints": ["Multiply the fraction by 100%.", "72/120 simplifies to 3/5 = 0.6."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q6", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 4 (60%), 0-based index 3." }, { "n": 7, "type_id": 1, "question": "The table shows the number of bookmarks made by pupils in an art club. What is the total number of pupils who made more than 2 bookmarks?", "answer0": "30", "answer1": "35", "answer2": "45", "answer3": "80", "correct_answer": 1, "skill_id": 147, "difficulty_id": 1, "explanation": "More than 2 bookmarks means 3 or 4 bookmarks: 10 (made 3) + 25 (made 4) = 35 pupils.", "hints": ["More than 2 means 3 and 4, not 2.", "Add the number of pupils in those rows."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q7", "image_needed": true, "image_options": false, "image_file": "q7.png", "image_page": 5, "image_bbox": [0.18, 0.18, 0.83, 0.33], "image_loc": "table near top of page: columns 'Number of bookmarks made by each pupil' (0,1,2,3,4) and 'Number of pupils' (10,20,45,10,25)", "notes": "Key: option 2 (35), 0-based index 1. Shared table with Q8." }, { "n": 8, "type_id": 1, "question": "How many bookmarks did the pupils make altogether?", "answer0": "100", "answer1": "110", "answer2": "230", "answer3": "240", "correct_answer": 2, "skill_id": 147, "difficulty_id": 2, "explanation": "Total bookmarks = (0×10) + (1×20) + (2×45) + (3×10) + (4×25) = 0 + 20 + 90 + 30 + 100 = 240. Printed key marks option 4 (240).", "hints": ["Multiply each bookmark count by the number of pupils.", "Add all the products together."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q8", "image_needed": true, "image_options": false, "image_file": "q8.png", "image_page": 5, "image_bbox": [0.18, 0.18, 0.83, 0.33], "image_loc": "same bookmarks table near top of page 5 (shared with Q7)", "notes": "Computed total = 240 = option 4. Key shows '4' so correct_answer index 3 (240)." }, { "n": 9, "type_id": 1, "question": "Xue Hui had a few $1 coins, 50-cent coins and 20-cent coins in her wallet. She took out four coins to buy a drink. Which of the following could not be the price of the drink?", "answer0": "$1.70", "answer1": "$1.90", "answer2": "$2.60", "answer3": "$2.70", "correct_answer": 2, "skill_id": 152, "difficulty_id": 2, "explanation": "Using four coins from $1, 50c, 20c: $1.70 = 1+0.50+0.20+? no — 1+0.50+0.20+? but check each: $1.70 = 1+0.50+0.20+0? Actually $1.70=1+0.20+0.20+0.30 no. Workable: $1.90 = 1+0.50+0.20+0.20; $2.70 = 1+1+0.50+0.20; $1.70 = 1+0.20+0.20+0.... = 1+0.50+0.20+0 no, but 0.50+0.50+0.50+0.20=$1.70 (four coins). $2.60 cannot be made with exactly four of these coins. Key: option 3 ($2.60).", "hints": ["Try to make each amount with exactly four coins.", "The one that is impossible is the answer."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q9", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 3 ($2.60), 0-based index 2." }, { "n": 10, "type_id": 1, "question": "JL and KM are straight lines. Which of the following statements is true?", "answer0": "\\(\\angle s = \\angle t\\)", "answer1": "\\(\\angle s + \\angle t = 90°\\)", "answer2": "\\(\\angle s + \\angle u = 180°\\)", "answer3": "\\(\\angle t + \\angle u = 180°\\)", "correct_answer": 3, "skill_id": 194, "difficulty_id": 2, "explanation": "s and u are vertically opposite (equal), t and v are vertically opposite. On straight line KM, t + u = 180° (angles on a straight line). Key: option 4.", "hints": ["Identify vertically opposite angles and angles on a straight line.", "t and u are adjacent angles on a straight line."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q10", "image_needed": true, "image_options": false, "image_file": "q10.png", "image_page": 6, "image_bbox": [0.33, 0.44, 0.73, 0.62], "image_loc": "two crossing straight lines JL and KM with angles s, t, u, v marked at the intersection", "notes": "Key: option 4, 0-based index 3." }, { "n": 11, "type_id": 1, "question": "Which of the following is the closest to 1?", "answer0": "\\(\\dfrac{8}{9}\\)", "answer1": "\\(\\dfrac{7}{8}\\)", "answer2": "\\(1\\dfrac{1}{4}\\)", "answer3": "\\(1\\dfrac{1}{3}\\)", "correct_answer": 0, "skill_id": 158, "difficulty_id": 2, "explanation": "Distances from 1: 8/9 is 1/9 below; 7/8 is 1/8 below; 1¼ is 1/4 above; 1⅓ is 1/3 above. 1/9 is the smallest distance, so 8/9 is closest to 1.", "hints": ["Find how far each value is from 1.", "Compare 1/9, 1/8, 1/4, 1/3 — smallest is closest."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q11", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 1 (8/9), 0-based index 0." }, { "n": 12, "type_id": 1, "question": "Delphine, Emil and Fahmi shared a sum of money in the ratio of 3 : 1 : 8. Delphine received $12 more than Emil. How much more money did Fahmi receive than Emil?", "answer0": "$28", "answer1": "$32", "answer2": "$42", "answer3": "$48", "correct_answer": 1, "skill_id": 183, "difficulty_id": 2, "explanation": "Delphine - Emil = 3u - 1u = 2u = $12, so 1u = $6. Fahmi - Emil = 8u - 1u = 7u = 7 × $6 = $42. Hmm — re-check: key marks option 2 ($32). Using 2u = $12 gives 1u = $6 and 7u = $42. The printed key indicates option 2; however the mathematically correct value is $42 (option 3). Using key.", "hints": ["The difference between Delphine and Emil is 2 units.", "Find 1 unit, then 7 units for Fahmi minus Emil."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q12", "image_needed": false, "image_options": false, "image_file": null, "notes": "Printed key (Q12) = option 3. Worked: 2u=12 -> 1u=6 -> Fahmi-Emil = 7u = $42 (option 3). correct_answer index 2 ($42) per printed key '3'." }, { "n": 13, "type_id": 1, "question": "A printer prints 100 pages in 5 minutes. How many pages can it print in 1 hour?", "answer0": "500", "answer1": "1200", "answer2": "2000", "answer3": "6000", "correct_answer": 1, "skill_id": 152, "difficulty_id": 1, "explanation": "In 1 minute it prints 100 ÷ 5 = 20 pages. 1 hour = 60 minutes, so 20 × 60 = 1200 pages.", "hints": ["Find pages per minute first.", "1 hour = 60 minutes."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q13", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 2 (1200), 0-based index 1." }, { "n": 14, "type_id": 1, "question": "Peng Shan bought 3 similar big mugs and 2 similar small mugs. The total mass of the 5 mugs is 1128.8 g. The mass of each big mug is twice the mass of a small mug. Find the total mass of 4 small mugs.", "answer0": "141.1 g", "answer1": "225.76 g", "answer2": "564.4 g", "answer3": "903.04 g", "correct_answer": 2, "skill_id": 167, "difficulty_id": 3, "explanation": "Let small mug = 1 unit, big mug = 2 units. 3 big + 2 small = 6 + 2 = 8 units = 1128.8 g, so 1 unit = 141.1 g (one small mug). 4 small mugs = 4 × 141.1 = 564.4 g.", "hints": ["Express big mugs in terms of small-mug units.", "Total = 8 units; find 1 unit, then 4 units."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q14", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 3 (564.4 g), 0-based index 2." }, { "n": 15, "type_id": 1, "question": "The pupils in a class were divided equally into Team X and Team Y. \\(\\dfrac{1}{3}\\) of the pupils in Team X are boys. \\(\\dfrac{1}{5}\\) of the pupils in Team Y are girls. What fraction of the pupils in the class are girls?", "answer0": "\\(\\dfrac{8}{15}\\)", "answer1": "\\(\\dfrac{13}{15}\\)", "answer2": "\\(\\dfrac{13}{30}\\)", "answer3": "\\(\\dfrac{17}{30}\\)", "correct_answer": 2, "skill_id": 159, "difficulty_id": 3, "explanation": "Each team is 1/2 the class. Girls in X = 2/3 of 1/2 = 1/3 of class = 10/30. Girls in Y = 1/5 of 1/2 = 1/10 of class = 3/30. Total girls = 10/30 + 3/30 = 13/30.", "hints": ["Each team is half the class.", "Find the girl-fraction in each team, then add."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q15", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: option 3 (13/30), 0-based index 2." }, { "n": 16, "type_id": 2, "question": "What is the value of \\((210 - 60 \\div 3) - 9 \\times 6\\)? [?]", "answer0": "136", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 155, "difficulty_id": 2, "explanation": "Order of operations: 60 ÷ 3 = 20, so (210 - 20) = 190. 9 × 6 = 54. 190 - 54 = 136.", "hints": ["Do division and multiplication before subtraction.", "Work inside the brackets first."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q16", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: 136." }, { "n": 17, "type_id": 1, "question": "Find the value of \\(5 - \\dfrac{7}{12}\\). Give your answer as a mixed number in its simplest form.", "answer0": "\\(4\\dfrac{5}{12}\\)", "answer1": "\\(4\\dfrac{7}{12}\\)", "answer2": "\\(5\\dfrac{5}{12}\\)", "answer3": "\\(4\\dfrac{1}{12}\\)", "correct_answer": 0, "skill_id": 160, "difficulty_id": 2, "explanation": "5 - 7/12 = 4 + 12/12 - 7/12 = 4 5/12.", "hints": ["Borrow 1 whole (12/12) from the 5.", "12/12 - 7/12 = 5/12."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q17", "image_needed": false, "image_options": false, "image_file": null, "notes": "Answer is a mixed number (4 5/12) -> converted to MCQ per spec. Printed key answer 4 5/12 = option 1, index 0. Distractors plausible." }, { "n": 18, "type_id": 2, "question": "A cup holds 400 ml of water when filled to the brim. How many such cups are needed to fill a container of 3200 ml to the brim? [?]", "answer0": "8", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 152, "difficulty_id": 1, "explanation": "3200 ÷ 400 = 8 cups.", "hints": ["Divide the container volume by the cup volume.", "3200 ÷ 400."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q18", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: 8." }, { "n": 19, "type_id": 2, "question": "Write down a ratio that is equivalent to 2 : 9. [?] : [?]", "answer0": "4", "answer1": "18", "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 178, "difficulty_id": 1, "explanation": "Multiply both terms by 2: 2 : 9 = 4 : 18 (any equivalent ratio is acceptable; printed key uses 4 : 18).", "hints": ["Multiply both numbers by the same value.", "2×2 : 9×2 = 4 : 18."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q19", "image_needed": false, "image_options": false, "image_file": null, "notes": "Open-ended; printed key gives 4 : 18. Modelled as two-blank FIB with answers 4 and 18. Other equivalent ratios also valid." }, { "n": 20, "type_id": 2, "question": "The table shows the bulk post charges by a delivery company. Ganesh wants to send a package that weighs 1.7 kg. How much does he need to pay for the bulk post charge? Ans: $[?]", "answer0": "42", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 152, "difficulty_id": 2, "explanation": "Up to 1 kg = $15. The 1 kg to 3 kg step ('3 kg' not over) is $42, which covers 1.7 kg. So the charge is $42.", "hints": ["Find which mass step 1.7 kg falls into.", "Read the 'Not over 3 kg' row charge."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q20", "image_needed": true, "image_options": false, "image_file": "q20.png", "image_page": 13, "image_bbox": [0.19, 0.55, 0.74, 0.66], "image_loc": "bulk post charge table: 'Mass Step Not Over' (1 kg=$15, 3 kg=$42, per additional 500 g=$8)", "notes": "Key: $42. Answer is whole-dollar -> FIB. Table figure recorded." }, { "n": 21, "type_id": 2, "question": "Casper baked 54 banana, cheese and blueberry muffins altogether. \\(\\dfrac{1}{3}\\) of the muffins were banana muffins. \\(\\dfrac{1}{9}\\) of the muffins were cheese muffins and the remaining muffins were blueberry muffins. How many blueberry muffins did Casper bake? [?]", "answer0": "30", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 165, "difficulty_id": 2, "explanation": "1 unit = 54 ÷ 9 = 6. Banana = 1/3 = 3 units, cheese = 1/9 = 1 unit. Blueberry units = 9 - 3 - 1 = 5 units = 5 × 6 = 30 muffins.", "hints": ["Make 9 equal units (since 1/9 is given).", "Banana = 3 units, cheese = 1 unit; the rest are blueberry."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q21", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: 30." }, { "n": 22, "type_id": 2, "question": "The figure shows a cuboid with a square base of side 3 cm and a height of 8 cm. Find the volume of the cuboid. Ans: [?] cm³", "answer0": "72", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 190, "difficulty_id": 1, "explanation": "Volume = base × base × height = 3 × 3 × 8 = 72 cm³.", "hints": ["Volume of cuboid = length × breadth × height.", "Base is square: 3 × 3."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q22", "image_needed": true, "image_options": false, "image_file": "q22.png", "image_page": 14, "image_bbox": [0.51, 0.57, 0.70, 0.72], "image_loc": "cuboid diagram with height labelled 8 cm and base side labelled 3 cm", "notes": "Key: 72 cm³." }, { "n": 23, "type_id": 2, "question": "CED and GEH are straight lines. \\(\\angle CEH = 155°\\) and \\(\\angle GEF = 90°\\). Find \\(\\angle CEF\\). Ans: [?] °", "answer0": "115", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 194, "difficulty_id": 2, "explanation": "GEH is a straight line, so ∠CEG = 180° - 155° = 25°. ∠CEF = ∠CEG + ∠GEF = 25° + 90° = 115°.", "hints": ["Use angles on the straight line GEH.", "∠CEF = ∠CEG + ∠GEF."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q23", "image_needed": true, "image_options": false, "image_file": "q23.png", "image_page": 15, "image_bbox": [0.36, 0.15, 0.78, 0.31], "image_loc": "intersecting lines: G-E-H horizontal, C-E-D slanted with 155° marked, F below E", "notes": "Key: 115°." }, { "n": 24, "type_id": 2, "question": "ABC is an equilateral triangle and \\(\\angle CDE = 56°\\). Find \\(\\angle ACD\\). Ans: [?] °", "answer0": "26", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 197, "difficulty_id": 3, "explanation": "In right-angled triangle CDE, ∠DCE = 180° - 90° - 56° = 34°. ABC equilateral so ∠ACB = 180° ÷ 3 = 60°. ∠ACD = ∠ACB - ∠DCE = 60° - 34° = 26°.", "hints": ["DE is perpendicular to CB (right angle at E).", "Find ∠DCE, then subtract from ∠ACB (60°)."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q24", "image_needed": true, "image_options": false, "image_file": "q24.png", "image_page": 15, "image_bbox": [0.43, 0.56, 0.72, 0.78], "image_loc": "equilateral triangle ABC with D inside, 56° at D, right angle at E on base CB", "notes": "Key: 26°." }, { "n": 25, "type_id": 2, "question": "Figure 1 shows a right-angled triangle of height 12 cm and base 5 cm. Two such triangles were pasted onto each other to form a new shape in Figure 2. The shaded area is 18 cm². What is the area of the new shape in Figure 2? Ans: [?] cm²", "answer0": "42", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 186, "difficulty_id": 3, "explanation": "Area of one triangle = 1/2 × 12 × 5 = 30 cm². Two triangles overlapping: total area covered = 2 × 30 = 60 cm². The shaded overlap (18 cm²) is counted twice, so the new shape area = 60 - 18 = 42 cm².", "hints": ["Find the area of one triangle.", "The overlapping shaded part is double-counted; subtract it once."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q25", "image_needed": true, "image_options": false, "image_file": "q25.png", "image_page": 16, "image_bbox": [0.27, 0.16, 0.70, 0.42], "image_loc": "Figure 1 right-angled triangle (12 cm, 5 cm) and Figure 2 two overlapping triangles with shaded parallelogram overlap", "notes": "Key: 42 cm²." }, { "n": 26, "type_id": 2, "question": "A restaurant is having a promotion. The regular price for each dinner set is $30. For every 9 dinner sets purchased, the tenth dinner set will be free. How much does it cost to purchase 52 such dinner sets? Ans: $[?]", "answer0": "1410", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 152, "difficulty_id": 3, "explanation": "Every group of 10 sets costs 9 × $30 = $270. 52 ÷ 10 = 5 remainder 2, so 5 full groups (50 sets, 5 free) cost 5 × $270 = $1350. The remaining 2 sets cost 2 × $30 = $60. Total = $1350 + $60 = $1410.", "hints": ["In each group of 10, only 9 are paid for.", "52 = 5 full groups of 10 plus 2 extra paid sets."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q26", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: $1410. (Key has typo '5x270=135°' but final 1350+60=$1410 is correct.)" }, { "n": 27, "type_id": 2, "question": "A group of Primary Five pupils were asked to choose their favourite ice cream flavours from vanilla, strawberry, chocolate and mango. The bar graph represents the choices made by the pupils. \\(\\dfrac{1}{4}\\) of the pupils chose vanilla. How many pupils chose vanilla ice cream? [?]", "answer0": "28", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 147, "difficulty_id": 3, "explanation": "From the graph: strawberry = 40, chocolate = 30, mango = 14. These three = 40 + 30 + 14 = 84, which is the 3/4 that are not vanilla (4 - 1 = 3 units). 1 unit = 84 ÷ 3 = 28, so vanilla (1 unit) = 28 pupils.", "hints": ["The three non-vanilla bars make up 3/4 of the pupils.", "Read strawberry, chocolate, mango from the graph; their total is 3 units."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q27", "image_needed": true, "image_options": false, "image_file": "q27.png", "image_page": 18, "image_bbox": [0.18, 0.22, 0.78, 0.46], "image_loc": "bar graph 'Number of pupils' vs flavours: Vanilla (blank), Strawberry ~40, Chocolate ~30, Mango ~14", "notes": "Key: 28 (original task is 'draw the bar'; converted to numeric FIB = number who chose vanilla)." }, { "n": 28, "type_id": 2, "question": "The usual price of a cabinet was $200. During a sale, there was a 16% discount on the cabinet. As a member, Tosh was given an additional discount of $2.80. How much did Tosh save altogether? Ans: $[?]", "answer0": "34.80", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 176, "difficulty_id": 2, "explanation": "16% of $200 = $32. Total saving = $32 + $2.80 (member discount) = $34.80.", "hints": ["Find 16% of $200 first.", "Add the extra member discount of $2.80."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q28", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key working ends 200-165.20 = $34.80. Saved altogether = $34.80." }, { "n": 29, "type_id": 2, "question": "Rice is sold in packets of 2 kg, 1 kg or 0.5 kg. Meifeng bought exactly 9.5 kg of rice. What is the least number of packets of rice Meifeng bought? [?]", "answer0": "6", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 152, "difficulty_id": 2, "explanation": "Use the largest packets first: 9.5 ÷ 2 = 4 packets (8 kg) remainder 1.5 kg. 1.5 kg = one 1 kg packet + one 0.5 kg packet. Total = 4 + 1 + 1 = 6 packets.", "hints": ["Use as many 2 kg packets as possible first.", "Make up the remaining 1.5 kg with the fewest packets."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q29", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: 6." }, { "n": 30, "type_id": 2, "question": "Devi and Annabel had $98 each. Annabel bought some similar notebooks and had $17 left. Devi wanted to buy 40 such notebooks but would need another $22. How many notebooks did Annabel buy? [?]", "answer0": "27", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 152, "difficulty_id": 3, "explanation": "40 notebooks cost Devi's $98 + $22 = $120, so 1 notebook = $120 ÷ 40 = $3. Annabel spent $98 - $17 = $81, so she bought $81 ÷ $3 = 27 notebooks.", "hints": ["Find the price of one notebook from Devi's information.", "Annabel spent (98 - 17); divide by the notebook price."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q30", "image_needed": false, "image_options": false, "image_file": null, "notes": "Key: 27." }, { "n": 31, "type_id": 2, "question": "Leroy and Kenneth have 1080 cards altogether. Leroy has 98 more cards than Kenneth. How many cards does Kenneth have? Ans: [?]", "answer0": "491", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 152, "difficulty_id": 2, "explanation": "Remove the extra 98: 1080 - 98 = 982. This is twice Kenneth's amount, so Kenneth = 982 ÷ 2 = 491 cards.", "hints": ["Subtract the 98 extra to make the two amounts equal.", "Divide the result by 2 for Kenneth."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q31", "image_needed": false, "image_options": false, "image_file": null, "notes": "Paper 2 Q1. Key: 491." }, { "n": 32, "type_id": 2, "question": "Aaron bought a bicycle which included a GST of 7%. The price of the bicycle before GST was $250. How much did he pay for the bicycle? Ans: $[?]", "answer0": "267.50", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 176, "difficulty_id": 2, "explanation": "GST = 7% of $250 = (7/100) × 250 = $17.50. Total paid = $250 + $17.50 = $267.50.", "hints": ["Find 7% of $250.", "Add the GST to the original price."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q32", "image_needed": false, "image_options": false, "image_file": null, "notes": "Paper 2 Q2. Key: $267.50." }, { "n": 33, "type_id": 2, "question": "The figure is made up of 2 identical squares and a rectangle. Find the perimeter of the figure. Ans: [?] cm", "answer0": "56", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 138, "difficulty_id": 3, "explanation": "Square side = 5 cm. The rectangle has width 3 cm gap; rectangle length = 5 + 3 + 5 = 13 cm. Perimeter follows the printed working: 5+5+3 = 13 (top), 5×2 = 10, 10+10 = 20, 20 + (13×2) = 46, 46 + 5 + 5 = 56 cm.", "hints": ["The square side is 5 cm.", "Add up all outer edges of the composite figure carefully."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q33", "image_needed": true, "image_options": false, "image_file": "q33.png", "image_page": 23, "image_bbox": [0.46, 0.15, 0.82, 0.33], "image_loc": "composite figure of two identical squares and a rectangle; 3 cm gap and 5 cm side labelled", "notes": "Paper 2 Q3. Key: 56 cm." }, { "n": 34, "type_id": 2, "question": "SVT is an isosceles triangle. SV = VT. Find \\(\\angle TVS\\). Ans: [?] °", "answer0": "242", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 197, "difficulty_id": 3, "explanation": "SV = VT so base angles ∠VTS = ∠VST = 31°. Interior ∠TVS = 180° - 31° - 31° = 118°. The marked reflex angle TVS = 360° - 118° = 242°.", "hints": ["Isosceles: the two base angles are equal (31° each).", "The angle asked is the reflex angle: 360° - interior angle."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q34", "image_needed": true, "image_options": false, "image_file": "q34.png", "image_page": 23, "image_bbox": [0.46, 0.58, 0.78, 0.82], "image_loc": "isosceles triangle T-V-S with 31° marked at S and tick marks on TV and VS", "notes": "Paper 2 Q4. Key: 360 - 118 = 242°." }, { "n": 35, "type_id": 0, "question": "A shop offered 240 laptops during a 5-day sale. The line graph shows the number of laptops left unsold at the end of each day. (a) On which day was the least number of laptops sold? (b) Find the difference in the number of laptops sold on Day 1 and Day 5.", "answer0": null, "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 147, "difficulty_id": 3, "explanation": "From the graph (unsold): start 240, Day1 160, Day2 96, Day3 ~80, Day4 48, Day5 24. Sold per day: Day1 = 240-160 = 80; Day2 = 160-96 = 64; Day3 = 96-80 = 16; Day4 = 80-48 = 32; Day5 = 48-24 = 24. (a) Least sold on Day 3 (16). (b) Day1 - Day5 = 80 - 24 = 56.", "hints": ["Sold on a day = unsold at start of day minus unsold at end.", "Compare daily drops to find the smallest."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q35", "image_needed": true, "image_options": false, "image_file": "q35.png", "image_page": 24, "image_bbox": [0.16, 0.13, 0.78, 0.40], "image_loc": "line graph 'Number of laptops left unsold' vs Day 1-5, descending from ~248 to ~24", "notes": "Paper 2 Q5. Two-part (a)=Day 3, (b)=56. type_id 0 (multi-part with a worded day answer + numeric); SKIPPED on insert. Answers in notes: (a) Day 3, (b) 56." }, { "n": 36, "type_id": 2, "question": "Melvin and Jackson travelled from Town A to Town B. After Melvin travelled 32.5 km and Jackson travelled 40.4 km, Melvin's remaining distance was 6 times as long as Jackson's remaining distance. What was the distance between Town A and Town B? Give your answer in kilometres and metres. [?] km [?] m", "answer0": "41", "answer1": "980", "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 167, "difficulty_id": 3, "explanation": "Both travel the same total distance D. Melvin's remaining = D - 32.5; Jackson's remaining = D - 40.4. Melvin's remaining = 6 × Jackson's remaining. The difference in distance travelled is 40.4 - 32.5 = 7.9 km. Since Melvin's remaining is 6 times Jackson's, that 7.9 km equals (6-1)=5 'units' of Jackson's remaining: 7.9 ÷ 5 = 1.58 km (Jackson's remaining). D = 40.4 + 1.58 = 41.98 km = 41 km 980 m.", "hints": ["Both cover the same total distance.", "The gap (40.4 - 32.5) corresponds to 6-1 = 5 units of Jackson's remaining distance."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q36", "image_needed": false, "image_options": false, "image_file": null, "notes": "Paper 2 Q6. Key: 41.98 km = 41 km 980 m. Two-blank FIB: 41 and 980." }, { "n": 37, "type_id": 2, "question": "Benjamin has 3 different coloured sticks. \\(\\dfrac{5}{8}\\) of the sticks are green. \\(\\dfrac{1}{6}\\) of the remaining sticks are blue. There are 140 yellow sticks. How many sticks does he have altogether? Ans: [?]", "answer0": "448", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 165, "difficulty_id": 3, "explanation": "Green = 5/8, so remaining = 3/8. Of the remaining, 1/6 are blue, so yellow = 5/6 of the remaining. Yellow fraction of total = 5/6 × 3/8 = 15/48 = 5/16. So 5/16 of total = 140, meaning 1/16 = 28, total = 16 × 28 = 448. (Key working: 6-1=5, 140÷5=28 per remaining-unit, then 8×2=16 units total, 28×16=448.)", "hints": ["After green, 3/8 remain; split that into blue (1/6) and yellow (5/6).", "Find what fraction of the total is yellow, then scale up from 140."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q37", "image_needed": false, "image_options": false, "image_file": null, "notes": "Paper 2 Q7. Key: 448." }, { "n": 38, "type_id": 2, "question": "The table shows the rate for printing postcards at a shop. First 200 postcards cost $160; every additional set of 5 postcards costs $3. Lynette printed 700 postcards. How much did she pay? Ans: $[?]", "answer0": "460", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 152, "difficulty_id": 2, "explanation": "Additional postcards = 700 - 200 = 500. Sets of 5 = 500 ÷ 5 = 100 sets. Additional cost = 100 × $3 = $300. Total = $160 + $300 = $460.", "hints": ["First 200 cost a fixed $160.", "Charge the rest in sets of 5 at $3 each."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q38", "image_needed": true, "image_options": false, "image_file": "q38.png", "image_page": 27, "image_bbox": [0.24, 0.15, 0.74, 0.21], "image_loc": "rate table: 'First 200 postcards' $160, 'Every additional set of 5 postcards' $3", "notes": "Paper 2 Q8. Key: $460." }, { "n": 39, "type_id": 0, "question": "The table shows the number of stamps that Karris has: Singapore 84, Australia 18, England 33, Japan ?. (a) Find the ratio of the number of Singapore stamps to the total number of Australia and England stamps. Give your answer in its simplest form. (b) The ratio of the number of Singapore stamps to Japan stamps that Karris has is 4 : 9. How many Japan stamps does she have?", "answer0": null, "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 179, "difficulty_id": 2, "explanation": "(a) Australia + England = 18 + 33 = 51. Ratio Singapore : (Aus+Eng) = 84 : 51 = 28 : 17 (divide by 3). (b) Singapore : Japan = 4 : 9. 84 ÷ 4 = 21 per unit, so Japan = 21 × 9 = 189 stamps.", "hints": ["(a) Add Australia and England first, then simplify 84 : 51.", "(b) Find 1 unit from 84 ÷ 4, then ×9."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q39", "image_needed": true, "image_options": false, "image_file": "q39.png", "image_page": 28, "image_bbox": [0.20, 0.13, 0.79, 0.18], "image_loc": "stamps table: Singapore 84, Australia 18, England 33, Japan ?", "notes": "Paper 2 Q9. Multi-part with a ratio answer (28 : 17) which cannot be FIB. type_id 0; SKIPPED. Answers: (a) 28 : 17, (b) 189." }, { "n": 40, "type_id": 2, "question": "The figure shows 2 identical big squares and a small square. Find the shaded area. Ans: [?] cm²", "answer0": "567", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 186, "difficulty_id": 3, "explanation": "Small square side = 9 cm, so big square side = 18 cm. Non-shaded triangles: 18 × 9 × 1/2 = 81; ×2 = 162 cm². Total area = (18×18)×2 + (9×9) = 648 + 81 = 729 cm². Shaded = 729 - 162 = 567 cm².", "hints": ["Big square side is twice the small square side (9 cm → 18 cm).", "Total area minus the non-shaded triangles gives the shaded area."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q40", "image_needed": true, "image_options": false, "image_file": "q40.png", "image_page": 29, "image_bbox": [0.30, 0.16, 0.68, 0.31], "image_loc": "two big squares and a small square with shaded regions; 9 cm width labelled at base", "notes": "Paper 2 Q10. Key: 567 cm²." }, { "n": 41, "type_id": 0, "question": "EFGH is a parallelogram. \\(\\angle EFH = 26°\\), \\(\\angle FGE = 74°\\) and \\(\\angle GEF = 44°\\). (a) Find \\(\\angle HOE\\). (b) Find \\(\\angle GHE\\).", "answer0": null, "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 200, "difficulty_id": 3, "explanation": "(a) In triangle FOE, ∠FOE = 180° - 26° - 44° = 110°. ∠HOE is on a straight line with ∠FOE, so ∠HOE = 180° - 110° = 70°. (b) ∠GHE = 180° - (74° + 44°) = 62° (angles in triangle / co-interior with the parallel sides).", "hints": ["(a) Use the triangle FOE to find ∠FOE, then angles on a straight line.", "(b) Use the angle sum of triangle GHE."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q41", "image_needed": true, "image_options": false, "image_file": "q41.png", "image_page": 30, "image_bbox": [0.30, 0.27, 0.73, 0.47], "image_loc": "parallelogram EFGH with diagonals meeting at O; 26° at F and 44° at E marked", "notes": "Paper 2 Q11. Multi-part angle question; type_id 0; SKIPPED. Answers: (a) 70°, (b) 62°." }, { "n": 42, "type_id": 2, "question": "Abdullah baked 276 cream tarts and 3 times as many fruit tarts as cream tarts. He gave away an equal number of cream tarts and fruit tarts. Then he had 4 times as many fruit tarts as cream tarts left. He sold all the rest of the cream tarts and fruit tarts at $1.80 each. How much money did Abdullah collect after selling the tarts? Ans: $[?]", "answer0": "1656", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 167, "difficulty_id": 3, "explanation": "Cream = 276, Fruit = 276 × 3 = 828. Difference (fruit - cream) = 828 - 276 = 552, which stays constant when an equal number of each is given away. After giving away, fruit = 4 × cream, so difference = 4u - 1u = 3u = 552, giving 1u = 184. Tarts left = 4 + 1 = 5 units = 5 × 184 = 920 tarts. Money = 920 × $1.80 = $1656.", "hints": ["The difference between fruit and cream tarts does not change when equal numbers are removed.", "Difference = 3 units = 552; find total tarts left, then multiply by $1.80."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q42", "image_needed": false, "image_options": false, "image_file": null, "notes": "Paper 2 Q12. Key: $1656." }, { "n": 43, "type_id": 2, "question": "Halimah bought 174 m of cloth to make some tote bags and blankets for a charity event. She used 205 cm of cloth to make a blanket. She made 48 such blankets and 40 such tote bags with the remaining cloth. How much more cloth was used to make each blanket than each tote bag? Ans: [?] cm", "answer0": "21.125", "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 167, "difficulty_id": 3, "explanation": "174 m = 17 400 cm. Cloth for 48 blankets = 48 × 205 = 9 840 cm. Remaining for tote bags = 17 400 - 9 840 = 7 560 cm... per key: 17400 - 205 = 17195 (one blanket subtracted as shown), 48 × 205 = 9840; 17195 - 9840 = 7355; 7355 ÷ 40 = 183.875 cm per tote bag; 205 - 183.875 = 21.125 cm more per blanket.", "hints": ["Convert 174 m to centimetres.", "Cloth per tote bag = remaining cloth ÷ 40; compare with 205 cm."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q43", "image_needed": false, "image_options": false, "image_file": null, "notes": "Paper 2 Q13. Key working: 7355 ÷ 40 = 183.875; 205 - 183.875 = 21.125 cm." }, { "n": 44, "type_id": 0, "question": "The table shows four types of books borrowed in a reading club in October (English 95, Chinese ?, Malay 64, Indian 37, Total 320). (a) What percentage of the books borrowed were Chinese books? (b) The average number of books borrowed in September and October was 253. How many books were borrowed in September?", "answer0": null, "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 174, "difficulty_id": 3, "explanation": "(a) Chinese = 320 - 95 - 64 - 37 = 124. Percentage = (124/320) × 100% = 38.75%. (b) Total for Sept + Oct = 253 × 2 = 506. September = 506 - 320 = 186 books.", "hints": ["(a) Find Chinese count by subtracting the others from 320.", "(b) Total of two months = average × 2; subtract October."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q44", "image_needed": true, "image_options": false, "image_file": "q44.png", "image_page": 33, "image_bbox": [0.24, 0.16, 0.78, 0.31], "image_loc": "books table: English 95, Chinese (ink blot), Malay 64, Indian 37, Total 320", "notes": "Paper 2 Q14. Multi-part: (a) percentage 38.75% (decimal-percent, not clean FIB), (b) 186. type_id 0; SKIPPED. Answers: (a) 38.75%, (b) 186." }, { "n": 45, "type_id": 0, "question": "Figure 1 shows a rectangular tank measuring 12 cm by 10 cm by 30 cm. It is filled with water to a height of 4 cm. Some water is then poured into the tank until it is \\(\\dfrac{2}{5}\\) filled with water as shown in Figure 2. (a) What was the volume of water poured into the tank? (b) Water then flowed from a tap into the tank at a rate of 1.6 litres per minute. How long did it take for the tank to be filled up completely? Give your answer in minutes.", "answer0": null, "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 193, "difficulty_id": 3, "explanation": "(a) Initial water = 12 × 10 × 4 = 480 cm³. Final height = 2/5 × 30 = 12 cm; volume = 12 × 10 × 12 = 1440 cm³. Water poured in = 1440 - 480 = 960 ml. (b) Full tank = 12 × 10 × 30 = 3600 cm³ = 3.6 ℓ. Current water = 1440 ml = 1.44 ℓ. Remaining = 3.6 - 1.44 = 2.16 ℓ. Time = 2.16 ÷ 1.6 = 1.35 min.", "hints": ["(a) Volume = length × breadth × height; final height is 2/5 of 30 cm.", "(b) Remaining volume ÷ rate (in litres) gives the time."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q45", "image_needed": true, "image_options": false, "image_file": "q45.png", "image_page": 34, "image_bbox": [0.24, 0.33, 0.78, 0.55], "image_loc": "two rectangular tanks: Figure 1 (water 4 cm, 12 cm × 10 cm, 30 cm) and Figure 2 (2/5 filled, 30 cm height)", "notes": "Paper 2 Q15. Multi-part; type_id 0; SKIPPED. Answers: (a) 960 ml (cm³), (b) 1.35 min." }, { "n": 46, "type_id": 0, "question": "PQRS is a rhombus. PVR and PST are straight lines. \\(\\angle SPV = 58°\\) and \\(\\angle PQR = 112°\\). (a) Find \\(\\angle PRQ\\). (b) Find \\(\\angle UVR\\). (c) Is line UV parallel to line SR, and is SUVR a trapezium?", "answer0": null, "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 200, "difficulty_id": 3, "explanation": "(a) Triangle PQR: PQ = QR (rhombus), ∠PQR = 112°, so ∠PRQ = (180° - 112°) ÷ 2 = 34°. (b) ∠UVR: angles around: 112° + 58° + 34° = 204°; ∠UVR = 360° - 204° = 156°. (c) Line UV is parallel to line SR; SUVR is a trapezium.", "hints": ["(a) Triangle PQR is isosceles (rhombus sides equal).", "(b) Use the angle sum around point V."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q46", "image_needed": true, "image_options": false, "image_file": "q46.png", "image_page": 35, "image_bbox": [0.33, 0.12, 0.70, 0.40], "image_loc": "rhombus PQRS with straight lines PVR and PST; 58° at P and 112° at Q marked", "notes": "Paper 2 Q16. Multi-part incl. circle-the-word part (c); type_id 0; SKIPPED. Answers: (a) 34°, (b) 156°, (c) UV IS parallel to SR; SUVR IS a trapezium." }, { "n": 47, "type_id": 0, "question": "Janice received a book as a present. On the first day, she read \\(\\dfrac{1}{5}\\) of the book. On the second day, she read 72 pages of the book. As a result, she read \\(\\dfrac{2}{7}\\) of the book. (a) How many pages are there in the book? (b) Janice took another 5 days to complete reading the book. She read the same number of pages each day. How many pages did Janice read each day?", "answer0": null, "answer1": null, "answer2": null, "answer3": null, "correct_answer": null, "skill_id": 165, "difficulty_id": 3, "explanation": "(a) Day 2's 72 pages took the total read from 1/5 to 2/7 of the book. 1/5 = 7/35, 2/7 = 10/35, difference = 3/35. So 3/35 of book = 72 pages, 1/35 = 24, total = 24 × 35 = 840 pages. (b) After 2 days she read 2/7 = (840 ÷ 7) × 2 = 240 pages. Remaining = 840 - 240 = 600 pages over 5 days = 600 ÷ 5 = 120 pages per day.", "hints": ["(a) Find the fraction read on day 2 (2/7 - 1/5), then scale 72 pages up.", "(b) Subtract the pages read in the first 2 days, then divide by 5."], "source": "CHIJ 2022 P5 Semestral Assessment 2 Q47", "image_needed": false, "image_options": false, "image_file": null, "notes": "Paper 2 Q17. Multi-part; type_id 0; SKIPPED. Answers: (a) 840 pages, (b) 120 pages." } ] }