{
  "paper": {
    "school": "ACS (Junior)",
    "year": 2025,
    "level": "P5",
    "label": "Weighted Assessment 3",
    "source_prefix": "ACS (Junior) 2025 P5 Weighted Assessment 3",
    "has_answer_key": true
  },
  "questions": [
    {
      "n": 1,
      "type_id": 1,
      "question": "Bala scored 48 out of 60 marks in a quiz. What percentage of the total marks did he score?",
      "answer0": "20%",
      "answer1": "48%",
      "answer2": "80%",
      "answer3": "96%",
      "correct_answer": 2,
      "skill_id": 171,
      "difficulty_id": 1,
      "explanation": "Percentage = \\(\\dfrac{48}{60} \\times 100\\% = 80\\%\\). Answer: 80% (option 3).",
      "hints": ["Write the score as a fraction of the total: \\(\\dfrac{48}{60}\\).", "Multiply by 100% to convert to a percentage."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q1",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q1 [1m]. Answer key: option 3 (80%)."
    },
    {
      "n": 2,
      "type_id": 1,
      "question": "The figure is made up of 12 identical squares. What percentage of the figure is shaded?",
      "answer0": "40%",
      "answer1": "50%",
      "answer2": "60%",
      "answer3": "70%",
      "correct_answer": 1,
      "skill_id": 171,
      "difficulty_id": 2,
      "explanation": "The shaded region (the full shaded squares plus the two half-square triangles that combine into whole squares) is equivalent to 6 of the 12 identical squares. So the shaded fraction = \\(\\dfrac{6}{12} = \\dfrac{1}{2} = 50\\%\\). Answer: 50% (option 2).",
      "hints": ["Count the shaded squares; combine the shaded triangles into whole squares.", "Write the shaded count as a fraction of 12 and convert to a percentage."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q2",
      "image_needed": true,
      "image_options": false,
      "image_file": "q2.png",
      "image_page": 2,
      "image_bbox": [0.27, 0.43, 0.46, 0.62],
      "notes": "Q2 [1m]. Grid of 12 identical squares with shaded squares and triangles; shaded = 6/12. Answer key: option 2 (50%)."
    },
    {
      "n": 3,
      "type_id": 1,
      "question": "A printer prints 58 pages in 2 minutes. At this rate, how many pages will the printer take in 6 minutes?",
      "answer0": "87 pages",
      "answer1": "116 pages",
      "answer2": "174 pages",
      "answer3": "348 pages",
      "correct_answer": 2,
      "skill_id": 152,
      "difficulty_id": 1,
      "explanation": "6 minutes is 3 times 2 minutes, so the printer prints \\(58 \\times 3 = 174\\) pages. Answer: 174 pages (option 3).",
      "hints": ["6 minutes is 3 lots of 2 minutes.", "Multiply 58 by 3."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q3",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q3 [1m]. Answer key: option 3 (174 pages)."
    },
    {
      "n": 4,
      "type_id": 1,
      "question": "Mr Ang bought 30 apples and 70 oranges. 20% of the apples and 30% of the oranges were rotten. What percentage of the fruits were rotten?",
      "answer0": "21%",
      "answer1": "25%",
      "answer2": "27%",
      "answer3": "50%",
      "correct_answer": 2,
      "skill_id": 174,
      "difficulty_id": 2,
      "explanation": "Rotten apples = \\(20\\% \\times 30 = 6\\). Rotten oranges = \\(30\\% \\times 70 = 21\\). Total rotten = \\(6 + 21 = 27\\) out of 100 fruits = 27%. Answer: 27% (option 3).",
      "hints": ["Find the number of rotten apples and rotten oranges separately.", "There are 100 fruits in all, so 27 rotten fruits = 27%."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q4",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q4 [2m]. Answer key: option 3 (27%)."
    },
    {
      "n": 5,
      "type_id": 1,
      "question": "AOB, COD and EOF are straight lines. \\(\\angle FOD = 42°\\). Find \\(\\angle AOC + \\angle BOE\\).",
      "answer0": "42°",
      "answer1": "84°",
      "answer2": "126°",
      "answer3": "138°",
      "correct_answer": 3,
      "skill_id": 194,
      "difficulty_id": 3,
      "explanation": "\\(\\angle AOC\\) is vertically opposite \\(\\angle BOD\\) and \\(\\angle BOE\\) is vertically opposite \\(\\angle AOF\\). Along the straight line EOF, \\(\\angle AOC + \\angle BOE\\) together with the two angles around \\(\\angle FOD = 42°\\) make up a straight angle pair, giving \\(\\angle AOC + \\angle BOE = 180° - 42° = 138°\\). Answer: 138° (option 4).",
      "hints": ["Use vertically opposite angles and angles on a straight line at point O.", "The required sum and \\(\\angle FOD\\) make 180°: \\(180° - 42°\\)."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q5",
      "image_needed": true,
      "image_options": false,
      "image_file": "q5.png",
      "image_page": 3,
      "image_bbox": [0.38, 0.49, 0.70, 0.70],
      "notes": "Q5 [2m]. Three straight lines AOB, COD, EOF through O with angle FOD = 42°. Answer key: option 4 (138°)."
    },
    {
      "n": 6,
      "type_id": 2,
      "question": "A dishwasher costs $1300. During a sale, David bought the dishwasher at a discount of 20%. How much was the discount?<br>Ans: $[?]",
      "answer0": "260",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 176,
      "difficulty_id": 1,
      "explanation": "Discount = \\(20\\% \\times \\$1300 = \\dfrac{20}{100} \\times 1300 = \\$260\\). Answer: $260.",
      "hints": ["Find 20% of $1300.", "\\(\\dfrac{20}{100} \\times 1300\\)."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q6",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q6 [1m]. Money answer -> FIB. Printed answer key has a typo: it shows '20/100 x 1300 = $2600'; the correct value is $260 (20% of $1300). Used $260."
    },
    {
      "n": 7,
      "type_id": 2,
      "question": "160 ℓ of water flows from a tap in 20 minutes. How many litres of water flow from the tap in 1 minute?<br>Ans: [?] ℓ",
      "answer0": "8",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 152,
      "difficulty_id": 1,
      "explanation": "Water in 1 minute = \\(160 \\div 20 = 8\\) ℓ. Answer: 8 ℓ.",
      "hints": ["Divide the total volume by the number of minutes.", "\\(160 \\div 20\\)."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q7",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q7 [1m]. Integer answer -> FIB. Answer key: 160/20 = 8 L."
    },
    {
      "n": 8,
      "type_id": 2,
      "question": "JK is a straight line. Find \\(\\angle n\\).<br>Ans: [?]°",
      "answer0": "97",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 194,
      "difficulty_id": 2,
      "explanation": "The angles on the straight line JK at the point add up to 180°. With the 83° angle given, \\(\\angle n = 180° - 83° = 97°\\). Answer: 97°.",
      "hints": ["Angles on a straight line add up to 180°.", "Subtract the 83° angle from 180°."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q8",
      "image_needed": true,
      "image_options": false,
      "image_file": "q8.png",
      "image_page": 4,
      "image_bbox": [0.30, 0.58, 0.62, 0.74],
      "notes": "Q8 [1m]. Straight line JK with marked angle 83° and unknown n; integer answer -> FIB. Answer key: 180 - 83 = 97°."
    },
    {
      "n": 9,
      "type_id": 2,
      "question": "Mdm Lim had some money. She spent $80 and had $45 left. What percentage of her money did she spend?<br>Ans: [?] %",
      "answer0": "64",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 171,
      "difficulty_id": 2,
      "explanation": "Total money = \\(80 + 45 = \\$125\\). Percentage spent = \\(\\dfrac{80}{125} \\times 100\\% = 64\\%\\). Answer: 64%.",
      "hints": ["First find her total money: spent + left.", "Percentage spent = \\(\\dfrac{80}{125} \\times 100\\%\\)."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q9",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q9 [2m]. Integer percentage answer -> FIB. Answer key working: 80+45=125, 80/125 x 100 = 64%."
    },
    {
      "n": 10,
      "type_id": 2,
      "question": "The parking charges at a carpark are $1.80 for the first hour and $1.50 for every additional 30 min or part thereof. Ken parked his car from 4 p.m. to 6.15 p.m. How much did he have to pay?<br>Ans: $[?]",
      "answer0": "6.30",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 175,
      "difficulty_id": 3,
      "explanation": "Ken parked for 2 h 15 min. The first hour costs $1.80, leaving 1 h 15 min = 75 min. Every 30 min or part thereof is $1.50, so 75 min counts as 3 blocks (30 + 30 + 15): \\(3 \\times \\$1.50 = \\$4.50\\). Total = \\(\\$1.80 + \\$4.50 = \\$6.30\\). Answer: $6.30.",
      "hints": ["First hour is $1.80; the remaining time is 1 h 15 min.", "Charge for each 30 min OR part thereof: 75 min = 3 blocks at $1.50."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q10",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q10 [2m]. Money answer -> FIB. Answer key working: 1.5 x 3 = 4.5, 4.5 + 1.8 = $6.30 (parked 2h15min; first hour $1.80, then 3 blocks of 30-min-or-part at $1.50)."
    },
    {
      "n": 11,
      "type_id": 2,
      "question": "Measure \\(\\angle w\\).<br>Ans: [?]°",
      "answer0": "65",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 194,
      "difficulty_id": 1,
      "explanation": "Using a protractor on the drawn angle, \\(\\angle w\\) measures 65°. Answer: 65°.",
      "hints": ["Place the centre of the protractor at the vertex and align the baseline with one arm.", "Read off the angle where the other arm crosses the scale."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q11",
      "image_needed": true,
      "image_options": false,
      "image_file": "q11.png",
      "image_page": 6,
      "image_bbox": [0.38, 0.20, 0.62, 0.36],
      "notes": "Q11(a) [1m]. Measure-the-angle task; definite value -> FIB. Answer key: 65°. Figure: angle w drawn for measuring."
    },
    {
      "n": 12,
      "type_id": 2,
      "question": "AB is a straight line. Find \\(\\angle x\\).<br>Ans: [?]°",
      "answer0": "29",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 194,
      "difficulty_id": 2,
      "explanation": "Along the straight line AB, the 119° angle and its adjacent angle add to 180°, so that adjacent angle = \\(180° - 119° = 61°\\). The marked right angle (90°) is split into \\(\\angle x\\) and this 61°, so \\(\\angle x = 90° - 61° = 29°\\). Answer: 29°.",
      "hints": ["Use angles on the straight line AB: \\(180° - 119° = 61°\\).", "A right angle (90°) contains \\(\\angle x\\) and the 61° angle, so \\(\\angle x = 90° - 61°\\)."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q11",
      "image_needed": true,
      "image_options": false,
      "image_file": "q12.png",
      "image_page": 6,
      "image_bbox": [0.34, 0.48, 0.64, 0.68],
      "notes": "Q11(b) [2m]. Straight line AB with 119°, a right angle, and unknown x; integer answer -> FIB. Answer key working: 180-119=61, 90-61=29°."
    },
    {
      "n": 13,
      "type_id": 2,
      "question": "4000 people were at a stadium watching a football match. 60% of the people were adults and the rest were children. During half time, 25% of the children and some adults left the stadium. After half time, 50% of the remaining people were children. How many children left the stadium during half time?<br>Ans: [?]",
      "answer0": "400",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 175,
      "difficulty_id": 3,
      "explanation": "Children at first = \\(40\\% \\times 4000 = 1600\\). 25% of the children left: \\(25\\% \\times 1600 = 400\\) children. Answer: 400. (Using the key's method: \\(4000 \\div 10 = 400\\) is 10%, children = \\(400 \\times 4 = 1600\\), and \\(1600 \\div 4 = 400\\) children left.)",
      "hints": ["Children at first = 40% of 4000 = 1600.", "Children who left = 25% of 1600."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q12",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q12(a) [2m]. Integer answer -> FIB. Answer key working: 4000/10=400, 400x4=1600, 1600/4=400 children left."
    },
    {
      "n": 14,
      "type_id": 2,
      "question": "4000 people were at a stadium watching a football match. 60% of the people were adults and the rest were children. During half time, 25% of the children and some adults left the stadium. After half time, 50% of the remaining people were children. How many adults left the stadium during half time?<br>Ans: [?]",
      "answer0": "1200",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 175,
      "difficulty_id": 3,
      "explanation": "Children remaining after half time = \\(1600 - 400 = 1200\\). Since these are 50% of the remaining people, the remaining people = \\(1200 \\times 2 = 2400\\), with 1200 adults. Adults at first = \\(60\\% \\times 4000 = 2400\\), so adults who left = \\(2400 - 1200 = 1200\\). Answer: 1200.",
      "hints": ["Children remaining = 1600 - 400 = 1200, and these are half the remaining people.", "Remaining people = 2400, so remaining adults = 1200; subtract from the original 2400 adults."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q12",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q12(b) [2m]. Integer answer -> FIB. Answer key working: 1200 children remain = 50% so 2400 remain total -> 1200 adults remain; 2400 - 1200 = 1200 adults left."
    },
    {
      "n": 15,
      "type_id": 1,
      "question": "Two printing machines, Machine X and Machine Y, were used together to print a batch of books. When working together, both machines took 3 hours to complete the printing. When only Machine X is used, it needs 8 hours to print the same batch of books. How long would it take if only Machine Y is used?",
      "answer0": "\\(4\\dfrac{4}{5}\\) h",
      "answer1": "\\(5\\dfrac{1}{3}\\) h",
      "answer2": "\\(2\\dfrac{2}{3}\\) h",
      "answer3": "\\(5\\) h",
      "correct_answer": 0,
      "skill_id": 165,
      "difficulty_id": 3,
      "explanation": "Working together they finish in 3 h, so in 1 h they do \\(\\dfrac{1}{3}\\) of the job. Machine X alone takes 8 h, doing \\(\\dfrac{1}{8}\\) per hour. So Machine Y does \\(\\dfrac{1}{3} - \\dfrac{1}{8} = \\dfrac{8}{24} - \\dfrac{3}{24} = \\dfrac{5}{24}\\) per hour. Machine Y alone takes \\(1 \\div \\dfrac{5}{24} = \\dfrac{24}{5} = 4\\dfrac{4}{5}\\) hours. Answer: \\(4\\dfrac{4}{5}\\) h.",
      "hints": ["Find the fraction of the job done per hour together (\\(\\dfrac{1}{3}\\)) and by X alone (\\(\\dfrac{1}{8}\\)).", "Y's hourly rate = \\(\\dfrac{1}{3} - \\dfrac{1}{8} = \\dfrac{5}{24}\\); Y's time = \\(\\dfrac{24}{5}\\) hours."],
      "source": "ACS (Junior) 2025 P5 Weighted Assessment 3 Q13",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "image_page": null,
      "image_bbox": null,
      "notes": "Q13 [4m]. Answer is mixed number 4 4/5 h -> MCQ (not FIB). Answer key: 4 4/5 h. Distractors are plausible time values."
    }
  ]
}