{
  "paper": {
    "school": "Nan Hua",
    "year": 2025,
    "level": "P4",
    "label": "Weighted Assessment 2",
    "source_prefix": "Nan Hua 2025 P4 Weighted Assessment 2",
    "has_answer_key": true
  },
  "questions": [
    {
      "n": 1,
      "type_id": 1,
      "question": "Express the shaded part of the figure as an improper fraction.",
      "answer0": "$$\\frac{27}{8}$$",
      "answer1": "$$\\frac{29}{8}$$",
      "answer2": "$$3\\frac{3}{8}$$",
      "answer3": "$$3\\frac{5}{8}$$",
      "correct_answer": 1,
      "skill_id": 119,
      "difficulty_id": 1,
      "explanation": "Three whole circles are fully shaded and the fourth circle has 5 of its 8 parts shaded. Total = $$3\\frac{5}{8} = \\frac{3\\times8+5}{8} = \\frac{29}{8}$$. Answer: $$\\frac{29}{8}$$ (option 2).",
      "hints": ["Count the fully-shaded circles as whole numbers.", "The last circle is divided into 8 equal parts; count how many are shaded.", "Convert the mixed number to an improper fraction: multiply the whole number by the denominator and add the numerator."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q1",
      "image_needed": true,
      "image_options": false,
      "image_file": "q1.png",
      "image_page": 2,
      "image_bbox": [0.34, 0.27, 0.82, 0.35],
      "image_loc": "row of 4 circles near top of page; first three shaded, fourth divided into 8 sectors",
      "notes": "Key: option 2. 3 wholes + 5/8 = 29/8."
    },
    {
      "n": 2,
      "type_id": 1,
      "question": "What is the mixed number represented by the letter A on the number line?",
      "answer0": "$$\\frac{8}{5}$$",
      "answer1": "$$\\frac{23}{5}$$",
      "answer2": "$$4\\frac{3}{5}$$",
      "answer3": "$$4\\frac{4}{6}$$",
      "correct_answer": 2,
      "skill_id": 119,
      "difficulty_id": 1,
      "explanation": "Between 4 and 5 the number line is divided into 5 equal parts, so each part is $$\\frac{1}{5}$$. A is at the 3rd mark after 4, giving $$4\\frac{3}{5}$$ (option 3).",
      "hints": ["Count how many equal intervals lie between 4 and 5.", "Each interval is one-fifth.", "A is 3 intervals past 4."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q2",
      "image_needed": true,
      "image_options": false,
      "image_file": "q2.png",
      "image_page": 2,
      "image_bbox": [0.18, 0.59, 0.78, 0.67],
      "image_loc": "number line from 4 to 6 with arrow labelled A between 4 and 5",
      "notes": "Key: option 3. Number line 4-5 split into fifths; A at 4 3/5."
    },
    {
      "n": 3,
      "type_id": 1,
      "question": "Arrange the fractions in increasing order.<br>$$\\frac{15}{7}$$, $$1\\frac{4}{9}$$, $$\\frac{5}{3}$$",
      "answer0": "$$1\\frac{4}{9}$$, $$\\frac{15}{7}$$, $$\\frac{5}{3}$$",
      "answer1": "$$1\\frac{4}{9}$$, $$\\frac{5}{3}$$, $$\\frac{15}{7}$$",
      "answer2": "$$\\frac{15}{7}$$, $$\\frac{5}{3}$$, $$1\\frac{4}{9}$$",
      "answer3": "$$\\frac{5}{3}$$, $$\\frac{15}{7}$$, $$1\\frac{4}{9}$$",
      "correct_answer": 1,
      "skill_id": 119,
      "difficulty_id": 2,
      "explanation": "Convert to decimals: $$1\\frac{4}{9}\\approx1.44$$, $$\\frac{5}{3}\\approx1.67$$, $$\\frac{15}{7}\\approx2.14$$. Increasing order: $$1\\frac{4}{9}$$, $$\\frac{5}{3}$$, $$\\frac{15}{7}$$ (option 2).",
      "hints": ["Convert each fraction to a decimal or a common form to compare.", "$$1\\frac{4}{9}\\approx1.44$$, $$\\frac{5}{3}\\approx1.67$$, $$\\frac{15}{7}\\approx2.14$$.", "List from smallest to largest."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q3",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 2. Fractions shown as boxed values; reproduced in stem text."
    },
    {
      "n": 4,
      "type_id": 1,
      "question": "There are a total of 40 students in Class 4A. The table shows the number of students who wear glasses in Class 4A.<br>What is the number of girls in 4A who wear glasses?",
      "answer0": "8",
      "answer1": "9",
      "answer2": "10",
      "answer3": "19",
      "correct_answer": 0,
      "skill_id": 146,
      "difficulty_id": 2,
      "explanation": "Total girls = 40 − 21 (boys) = 19. Girls who do not wear glasses = 11, so girls who wear glasses = 19 − 11 = 8 (option 1).",
      "hints": ["Find the total number of girls: 40 − 21.", "Subtract the girls who do not wear glasses.", "19 − 11 = 8."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q4",
      "image_needed": true,
      "image_options": false,
      "image_file": "q4.png",
      "image_page": 3,
      "image_bbox": [0.17, 0.50, 0.66, 0.65],
      "image_loc": "3-row table with Boys/Girls columns: wear glasses (12, ?), do not wear glasses (?, 11), Total (21, ?)",
      "notes": "Key: option 1. Boys total 21, girls total 19; 19-11=8."
    },
    {
      "n": 5,
      "type_id": 1,
      "question": "How many more hearts need to be shaded so that $$\\frac{2}{3}$$ of the set of hearts is shaded?",
      "answer0": "7",
      "answer1": "2",
      "answer2": "3",
      "answer3": "10",
      "correct_answer": 0,
      "skill_id": 120,
      "difficulty_id": 2,
      "explanation": "There are 15 hearts. $$\\frac{2}{3}\\times15 = 10$$ hearts must be shaded. 3 are already shaded, so $$10 - 3 = 7$$ more are needed (option 1).",
      "hints": ["Count the total number of hearts (15).", "Two-thirds of 15 is 10.", "Subtract the hearts already shaded."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q5",
      "image_needed": true,
      "image_options": false,
      "image_file": "q5.png",
      "image_page": 4,
      "image_bbox": [0.36, 0.18, 0.80, 0.32],
      "image_loc": "3 rows x 5 hearts; 3 hearts shaded (positions row1-col1, row2-col2, row3-col3)",
      "notes": "Key: option 1. 15 hearts total, 3 already shaded, need 10 shaded → 7 more."
    },
    {
      "n": 6,
      "type_id": 1,
      "question": "Ms Lim is planning for a class party. She wants to buy enough pizza such that each of her 35 students can have $$\\frac{1}{6}$$ of a pizza. The shop only sells whole pizza. What is the least number of whole pizza Ms Lim need to buy?",
      "answer0": "5",
      "answer1": "6",
      "answer2": "7",
      "answer3": "4",
      "correct_answer": 1,
      "skill_id": 120,
      "difficulty_id": 2,
      "explanation": "Total pizza needed = $$35\\times\\frac{1}{6} = \\frac{35}{6} = 5\\frac{5}{6}$$ pizzas. Since only whole pizzas are sold, round up to 6 (option 2).",
      "hints": ["Multiply 35 by one-sixth to find the pizza needed.", "$$\\frac{35}{6} = 5\\frac{5}{6}$$.", "Round up to the next whole pizza."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q6",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 2. 35/6 = 5 5/6 → round up to 6."
    },
    {
      "n": 7,
      "type_id": 2,
      "question": "(a) Express $$\\frac{22}{4}$$ as a mixed number in its simplest form.<br>(b) $$\\frac{2}{9}$$ of 63 = [?]",
      "answer0": "5 1/2",
      "answer1": "14",
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 120,
      "difficulty_id": 2,
      "explanation": "(a) $$\\frac{22}{4} = 5\\frac{2}{4} = 5\\frac{1}{2}$$. (b) $$\\frac{2}{9}$$ of 63: $$63\\div9 = 7$$, then $$7\\times2 = 14$$.",
      "hints": ["(a) Divide 22 by 4 to get the whole number and remainder, then simplify the fraction.", "(b) First find one-ninth of 63 by dividing.", "(b) Multiply that result by 2."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q7",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: (a) 5 1/2; (b) 14. Two answer blanks (answer0=5 1/2, answer1=14)."
    },
    {
      "n": 8,
      "type_id": 2,
      "question": "Mdm Siti had 5 $$l$$ of orange juice. She drank $$\\frac{3}{8}$$ $$l$$ of orange juice. How much orange juice did she have left? [?]",
      "answer0": "4 5/8",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 121,
      "difficulty_id": 2,
      "explanation": "$$5 - \\frac{3}{8} = 4\\frac{8}{8} - \\frac{3}{8} = 4\\frac{5}{8}$$ litres.",
      "hints": ["Rename 5 as $$4\\frac{8}{8}$$ so you can subtract eighths.", "Subtract the numerators: $$\\frac{8}{8}-\\frac{3}{8}=\\frac{5}{8}$$.", "Answer in litres: $$4\\frac{5}{8}$$."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q8",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 4 5/8 l. Answer unit is litres."
    },
    {
      "n": 9,
      "type_id": 2,
      "question": "The line graph shows the hourly sales at a coffee stall on a Monday over 3 hours. What is the total amount of sales from 5 pm to 7 pm? $[?]",
      "answer0": "900",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 147,
      "difficulty_id": 2,
      "explanation": "From the graph: 5 pm = $140, 6 pm = $400, 7 pm = $360. Total = $$140 + 400 + 360 = 900$$ dollars.",
      "hints": ["Read the sales value at 5 pm, 6 pm and 7 pm from the graph.", "5 pm = $140, 6 pm = $400, 7 pm = $360.", "Add the three amounts."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q9",
      "image_needed": true,
      "image_options": false,
      "image_file": "q9.png",
      "image_page": 6,
      "image_bbox": [0.25, 0.18, 0.78, 0.42],
      "image_loc": "line graph 'Hourly sales at a coffee stall', x-axis 4-7 pm, y-axis Sales ($) 0-500",
      "notes": "Key: $900. Answer is a dollar amount (140+400+360)."
    },
    {
      "n": 10,
      "type_id": 2,
      "question": "The bar graph shows the number of boys and girls in Class 4A. There are 15 more girls than boys in Class 4A. What is the total number of students in Class 4A? [?]",
      "answer0": "39",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 148,
      "difficulty_id": 2,
      "explanation": "From the bar graph the boys bar is 2 units and the girls bar is 7 units, a difference of 5 units = 15, so 1 unit = 3 students. Boys = 2×6 = 12 and girls = 12 + 15 = 27. Total = 12 + 27 = 39 students.",
      "hints": ["Use the scale of the bar graph to read the number of boys.", "Girls = boys + 15.", "Add boys and girls for the total."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q10",
      "image_needed": true,
      "image_options": false,
      "image_file": "q10.png",
      "image_page": 7,
      "image_bbox": [0.40, 0.21, 0.74, 0.42],
      "image_loc": "bar graph titled 'Class 4A' with two bars Boys and Girls, y-axis 'Number of students'",
      "notes": "Key: 39 students (boys 12, girls 27)."
    },
    {
      "n": 11,
      "type_id": 2,
      "question": "The line graph shows the mass of recyclables collected from Primary 4 classes over 5 months.<br>(a) Which month had the least mass of recyclables collected? [?]<br>(b) During which 1-month period was the increase in the mass of recyclables collected the greatest? [?] to [?]",
      "answer0": "February",
      "answer1": "April",
      "answer2": "May",
      "answer3": null,
      "correct_answer": null,
      "skill_id": 147,
      "difficulty_id": 2,
      "explanation": "(a) The lowest point on the line graph is at February (about 45 kg). (b) The steepest upward segment is from April (~90 kg) to May (~135 kg), the greatest 1-month increase.",
      "hints": ["(a) Find the lowest point on the line.", "(b) Look for the steepest upward segment between two consecutive months.", "(b) Compare the rise between each pair of months."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q11",
      "image_needed": true,
      "image_options": false,
      "image_file": "q11.png",
      "image_page": 8,
      "image_bbox": [0.24, 0.30, 0.80, 0.53],
      "image_loc": "line graph 'Recyclables collected from P4 classes', x-axis Jan-May, y-axis Mass of recyclables (Kg) 0-150",
      "notes": "Key: (a) February; (b) April to May. Three blanks (answer0=February, answer1=April, answer2=May)."
    },
    {
      "n": 12,
      "type_id": 2,
      "question": "Alice jogs $$\\frac{3}{4}$$ $$km$$ at a park. She walks $$\\frac{5}{12}$$ $$km$$ less than the distance she jogs. What is the total distance she jogs and walks? [?]",
      "answer0": "1 1/12",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 122,
      "difficulty_id": 3,
      "explanation": "Walk = $$\\frac{3}{4} - \\frac{5}{12} = \\frac{9}{12} - \\frac{5}{12} = \\frac{4}{12}$$ km. Total = $$\\frac{3}{4} + \\frac{4}{12} = \\frac{9}{12} + \\frac{4}{12} = \\frac{13}{12} = 1\\frac{1}{12}$$ km.",
      "hints": ["First find the walking distance: jog distance minus 5/12.", "Use a common denominator of 12.", "Add the jog and walk distances, then convert to a mixed number."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q12",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 1 1/12 km. Answer unit is km."
    },
    {
      "n": 13,
      "type_id": 2,
      "question": "A box is filled with some balls. $$\\frac{4}{11}$$ of the balls are yellow and the rest of the balls are red. There are 42 more red balls than yellow balls. How many balls are there in the box altogether? [?]",
      "answer0": "154",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 122,
      "difficulty_id": 3,
      "explanation": "Yellow = 4 units, red = 11 − 4 = 7 units. Difference = 7 − 4 = 3 units = 42, so 1 unit = 14. Total = 11 units = 14 × 11 = 154 balls.",
      "hints": ["Let the box be 11 equal units; yellow is 4 units.", "Red is the remaining 7 units; the difference is 3 units.", "3 units = 42, so 1 unit = 14 and total = 11 units."],
      "source": "Nan Hua 2025 P4 Weighted Assessment 2 Q13",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 154 balls."
    }
  ]
}