{
  "paper": {
    "school": "St Hilda",
    "year": 2025,
    "level": "P4",
    "label": "End-of-Year Exam",
    "source_prefix": "St Hilda 2025 P4 End-of-Year Exam",
    "has_answer_key": true
  },
  "questions": [
    {
      "n": 1,
      "type_id": 1,
      "question": "In which of the following does the digit 8 stand for 800?",
      "answer0": "4058",
      "answer1": "5084",
      "answer2": "5840",
      "answer3": "8504",
      "correct_answer": 2,
      "skill_id": 105,
      "difficulty_id": 1,
      "explanation": "The digit 8 stands for 800 when it sits in the hundreds place. In 5840, the 8 is in the hundreds place, so it stands for 800. In 4058 it is 8, in 5084 it is 80, in 8504 it is 8000.",
      "hints": ["Look at the place value of the digit 8 in each number.", "Hundreds place = third digit from the right."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q1",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 3 (1-based) = index 2"
    },
    {
      "n": 2,
      "type_id": 1,
      "question": "45 879 rounded to the nearest hundred is ____________.",
      "answer0": "45 800",
      "answer1": "45 880",
      "answer2": "45 900",
      "answer3": "46 000",
      "correct_answer": 2,
      "skill_id": 109,
      "difficulty_id": 1,
      "explanation": "To round 45 879 to the nearest hundred, look at the tens digit (7). Since 7 is 5 or more, round the hundreds up: 45 879 rounds to 45 900.",
      "hints": ["Look at the tens digit to decide rounding.", "If the tens digit is 5 or more, round the hundreds up."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q2",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 3 (1-based) = index 2"
    },
    {
      "n": 3,
      "type_id": 1,
      "question": "Arrange these fractions from the smallest to the greatest.<br>$$\\frac{1}{2}$$ , $$\\frac{4}{9}$$ , $$\\frac{8}{9}$$",
      "answer0": "$$\\frac{1}{2}$$ , $$\\frac{4}{9}$$ , $$\\frac{8}{9}$$",
      "answer1": "$$\\frac{4}{9}$$ , $$\\frac{1}{2}$$ , $$\\frac{8}{9}$$",
      "answer2": "$$\\frac{8}{9}$$ , $$\\frac{4}{9}$$ , $$\\frac{1}{2}$$",
      "answer3": "$$\\frac{4}{9}$$ , $$\\frac{8}{9}$$ , $$\\frac{1}{2}$$",
      "correct_answer": 1,
      "skill_id": 79,
      "difficulty_id": 2,
      "explanation": "Compare the fractions: 4/9 is just under a half (4.5/9 = 1/2), so 4/9 < 1/2. And 8/9 is the largest. Ordered smallest to greatest: 4/9, 1/2, 8/9.",
      "hints": ["Convert to a common denominator or compare each to 1/2.", "4/9 is less than 1/2 because half of 9 is 4.5."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q3",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 2 (1-based) = index 1"
    },
    {
      "n": 4,
      "type_id": 1,
      "question": "Which of the following shows $$\\frac{1}{5}$$ of the figure shaded?",
      "answer0": "Figure 1",
      "answer1": "Figure 2",
      "answer2": "Figure 3",
      "answer3": "Figure 4",
      "correct_answer": 1,
      "skill_id": 41,
      "difficulty_id": 1,
      "explanation": "The figure that is divided into 5 equal parts with exactly 1 part shaded shows 1/5. Option 2 has 5 equal strips with 1 shaded.",
      "hints": ["1/5 means 1 part shaded out of 5 equal parts.", "Count the total number of equal parts first."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q4",
      "image_needed": true,
      "image_options": true,
      "image_file": "q4.png",
      "image_page": 3,
      "image_bbox": [0.20, 0.14, 0.42, 0.58],
      "image_loc": "left side of page, four shaded-strip option figures stacked vertically labelled (1)-(4)",
      "notes": "Key: option 2 (1-based) = index 1. Image-option MCQ: each option is a strip figure. Options stacked vertically; downstream may need q4_opt0..3 crops."
    },
    {
      "n": 5,
      "type_id": 1,
      "question": "Which decimal is the smallest?",
      "answer0": "3.07",
      "answer1": "3.15",
      "answer2": "3.038",
      "answer3": "3.304",
      "correct_answer": 2,
      "skill_id": 124,
      "difficulty_id": 1,
      "explanation": "Compare the decimals by place value. 3.038 has 0 tenths and 3 hundredths, the smallest of all. 3.07 = 3.070, 3.15, 3.304 are all larger. So 3.038 is smallest.",
      "hints": ["Line up the decimal points and compare digit by digit.", "Compare the tenths place first."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q5",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 3 (1-based) = index 2"
    },
    {
      "n": 6,
      "type_id": 1,
      "question": "Write $$4\\frac{7}{20}$$ as a decimal.",
      "answer0": "4.7",
      "answer1": "4.27",
      "answer2": "4.35",
      "answer3": "4.72",
      "correct_answer": 2,
      "skill_id": 127,
      "difficulty_id": 2,
      "explanation": "Convert 7/20 to a decimal: multiply numerator and denominator by 5 to get 35/100 = 0.35. So 4 7/20 = 4.35.",
      "hints": ["Make the denominator 100: 7/20 = 35/100.", "35/100 = 0.35."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q6",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 3 (1-based) = index 2"
    },
    {
      "n": 7,
      "type_id": 1,
      "question": "Square X and Rectangle Y have the same perimeter. Find the length of each side of Square X.",
      "answer0": "8 cm",
      "answer1": "16 cm",
      "answer2": "32 cm",
      "answer3": "64 cm",
      "correct_answer": 1,
      "skill_id": 137,
      "difficulty_id": 2,
      "explanation": "Perimeter of Rectangle Y = 2 x (25 + 7) = 2 x 32 = 64 cm. Square X has the same perimeter, 64 cm. Each side = 64 div 4 = 16 cm.",
      "hints": ["Perimeter of a rectangle = 2 x (length + breadth).", "Each side of a square = perimeter div 4."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q7",
      "image_needed": true,
      "image_options": false,
      "image_file": "q7.png",
      "image_page": 4,
      "image_bbox": [0.20, 0.47, 0.72, 0.62],
      "image_loc": "middle of page, square X on left and rectangle Y (25 cm by 7 cm) on right",
      "notes": "Key: option 2 (1-based) = index 1"
    },
    {
      "n": 8,
      "type_id": 1,
      "question": "One of the angles is an acute angle. Identify the acute angle.",
      "answer0": "$$\\angle ABC$$",
      "answer1": "$$\\angle BCD$$",
      "answer2": "$$\\angle CDA$$",
      "answer3": "$$\\angle DAB$$",
      "correct_answer": 3,
      "skill_id": 139,
      "difficulty_id": 2,
      "explanation": "An acute angle is smaller than a right angle (less than 90 degrees). In the quadrilateral ABCD, angle DAB at vertex A is the only angle smaller than 90 degrees.",
      "hints": ["An acute angle is less than 90 degrees (smaller than a square corner).", "Compare each marked angle to a right angle."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q8",
      "image_needed": true,
      "image_options": false,
      "image_file": "q8.png",
      "image_page": 5,
      "image_bbox": [0.28, 0.15, 0.72, 0.34],
      "image_loc": "upper middle of page, quadrilateral ABCD with marked angles at each vertex",
      "notes": "Key: option 4 (1-based) = index 3"
    },
    {
      "n": 9,
      "type_id": 1,
      "question": "Adam is below 10 years old. His age is a factor of 28 and a multiple of 4. How old is he?",
      "answer0": "1",
      "answer1": "2",
      "answer2": "8",
      "answer3": "4",
      "correct_answer": 3,
      "skill_id": 111,
      "difficulty_id": 2,
      "explanation": "Factors of 28 below 10: 1, 2, 4, 7. Of these, the multiples of 4 are: 4. So Adam is 4 years old. (8 is a multiple of 4 but not a factor of 28.)",
      "hints": ["List the factors of 28: 1, 2, 4, 7, 14, 28.", "Which factor below 10 is also a multiple of 4?"],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q9",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 4 (1-based) = index 3 (answer 4)"
    },
    {
      "n": 10,
      "type_id": 1,
      "question": "In a library, there were 2580 fiction books. The number of non-fiction books was 3 times the number of fiction books. How many books were there altogether?",
      "answer0": "860",
      "answer1": "2583",
      "answer2": "7740",
      "answer3": "10 320",
      "correct_answer": 3,
      "skill_id": 118,
      "difficulty_id": 2,
      "explanation": "Non-fiction = 3 x 2580 = 7740. Altogether = 2580 + 7740 = 10 320 books.",
      "hints": ["First find the number of non-fiction books.", "Add fiction and non-fiction together."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q10",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 4 (1-based) = index 3"
    },
    {
      "n": 11,
      "type_id": 1,
      "question": "Mrs Lim had some money. After buying 48 toy planes at $367 each, she had $10 left. How much money did she have at first?",
      "answer0": "$4404",
      "answer1": "$4414",
      "answer2": "$17 616",
      "answer3": "$17 626",
      "correct_answer": 3,
      "skill_id": 118,
      "difficulty_id": 2,
      "explanation": "Cost of planes = 48 x $367 = $17 616. She had $10 left, so at first = $17 616 + $10 = $17 626.",
      "hints": ["First find the total cost of the 48 planes.", "Add the $10 she had left."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q11",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 4 (1-based) = index 3"
    },
    {
      "n": 12,
      "type_id": 1,
      "question": "Azri and Liying had the same number of stamps at first. After Azri gave away 60 stamps, Liying had 5 times as many stamps as Azri. How many stamps did Azri have at first?",
      "answer0": "15",
      "answer1": "65",
      "answer2": "75",
      "answer3": "300",
      "correct_answer": 2,
      "skill_id": 118,
      "difficulty_id": 3,
      "explanation": "Let Azri's amount after giving away be 1 unit; Liying = 5 units. They started equal, so the 60 given away is the difference: 5 units - 1 unit = 4 units = 60, so 1 unit = 15. Azri started with the same as Liying = 5 units = 75 stamps.",
      "hints": ["After giving away, the difference between them is the 60 stamps.", "Liying still has the original amount; that equals 5 units."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q12",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 3 (1-based) = index 2 (answer 75)"
    },
    {
      "n": 13,
      "type_id": 1,
      "question": "Mrs Lee used $$\\frac{3}{8}$$ kg of flour to bake cookies. The amount of flour used to bake a cake was $$\\frac{1}{5}$$ kg more than the amount used to bake cookies. How much flour did she use altogether?",
      "answer0": "$$\\frac{7}{21}$$ kg",
      "answer1": "$$\\frac{11}{20}$$ kg",
      "answer2": "$$\\frac{19}{20}$$ kg",
      "answer3": "$$\\frac{23}{40}$$ kg",
      "correct_answer": 2,
      "skill_id": 122,
      "difficulty_id": 3,
      "explanation": "Cake flour = 3/8 + 1/5 = 15/40 + 8/40 = 23/40 kg. Altogether = cookies + cake = 3/8 + 23/40 = 15/40 + 23/40 = 38/40 = 19/20 kg.",
      "hints": ["First find the flour used for the cake (3/8 + 1/5).", "Then add the cookie flour and the cake flour."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q13",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 3 (1-based) = index 2"
    },
    {
      "n": 14,
      "type_id": 1,
      "question": "A rope of length 20 m is cut into 8 equal pieces. How long is each piece?",
      "answer0": "0.25 m",
      "answer1": "0.4 m",
      "answer2": "2.5 m",
      "answer3": "16 m",
      "correct_answer": 2,
      "skill_id": 125,
      "difficulty_id": 1,
      "explanation": "Length of each piece = 20 div 8 = 2.5 m.",
      "hints": ["Divide the total length by the number of pieces.", "20 div 8 = 2.5."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q14",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 3 (1-based) = index 2"
    },
    {
      "n": 15,
      "type_id": 1,
      "question": "A decimal when rounded to the nearest whole number is 175. Which of the following is the smallest possible decimal?",
      "answer0": "174.49",
      "answer1": "174.50",
      "answer2": "175.49",
      "answer3": "175.50",
      "correct_answer": 1,
      "skill_id": 128,
      "difficulty_id": 2,
      "explanation": "To round to 175, the decimal must be at least 174.5 (rounds up) and below 175.5. 174.49 rounds to 174 (too small). 174.50 rounds up to 175 and is the smallest of the options that rounds to 175.",
      "hints": ["The smallest number that rounds up to 175 is 174.5.", "174.49 rounds down to 174, so it is too small."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q15",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: option 2 (1-based) = index 1"
    },
    {
      "n": 16,
      "type_id": 1,
      "question": "The figure is made up of a square and a rectangle. What is the perimeter of the figure?",
      "answer0": "28 m",
      "answer1": "34 m",
      "answer2": "37 m",
      "answer3": "40 m",
      "correct_answer": 1,
      "skill_id": 138,
      "difficulty_id": 3,
      "explanation": "The big rectangle is 10 m by 4 m. The small rectangle has area 9 m squared; its height equals its visible side. The small attached rectangle has one side 3 m (since 9 div 3 = 3, a 3 m by 3 m square). Perimeter of the composite = 10 + 4 + 3 + 3 + (10 - 3) + (4 + 3) traced around = 34 m.",
      "hints": ["The small piece has area 9 m squared; find its side lengths.", "Trace around the outside of the whole figure, adding every outer edge."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q16",
      "image_needed": true,
      "image_options": false,
      "image_file": "q16.png",
      "image_page": 7,
      "image_bbox": [0.28, 0.49, 0.62, 0.72],
      "image_loc": "middle of page, L-shaped figure: tall rectangle 10 m by 4 m with a smaller rectangle (Area = 9 m squared) attached on the right",
      "notes": "Key: option 2 (1-based) = index 1 (34 m)"
    },
    {
      "n": 17,
      "type_id": 1,
      "question": "The figure shows a rectangle and 2 identical squares. The length of each square is 4 cm. The length of the rectangle is twice the length of its breadth. What is the length of the rectangle?",
      "answer0": "16 cm",
      "answer1": "2 cm",
      "answer2": "8 cm",
      "answer3": "4 cm",
      "correct_answer": 0,
      "skill_id": 143,
      "difficulty_id": 2,
      "explanation": "The two stacked squares each have side 4 cm, so the breadth of the rectangle = 2 x 4 = 8 cm. The length is twice the breadth = 2 x 8 = 16 cm.",
      "hints": ["The breadth of the rectangle equals the combined height of the two squares.", "Length = 2 x breadth."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q17",
      "image_needed": true,
      "image_options": false,
      "image_file": "q17.png",
      "image_page": 8,
      "image_bbox": [0.30, 0.18, 0.68, 0.31],
      "image_loc": "upper middle of page, large rectangle (length marked ?) with two 4 cm squares stacked at the right end",
      "notes": "Key: option 1 (1-based) = index 0 (16 cm)"
    },
    {
      "n": 18,
      "type_id": 1,
      "question": "The table shows the number of students who take bus or train to school. The total number of students from 5A, 5B and 5C is 111. How many students from 5B take bus to school?",
      "answer0": "16",
      "answer1": "18",
      "answer2": "20",
      "answer3": "72",
      "correct_answer": 1,
      "skill_id": 148,
      "difficulty_id": 2,
      "explanation": "Known students = bus(22+17) + train(15+20+19) = 39 + 54 = 93. Total is 111, so the missing 5B bus value = 111 - 93 = 18.",
      "hints": ["Add up all the known numbers in the table.", "Subtract that sum from the total of 111."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q18",
      "image_needed": true,
      "image_options": false,
      "image_file": "q18.png",
      "image_page": 8,
      "image_bbox": [0.18, 0.55, 0.82, 0.67],
      "image_loc": "middle of page, 3-column table (5A, 5B, 5C) with rows for bus and train numbers; 5B bus cell shows ?",
      "notes": "Key: option 2 (1-based) = index 1 (18)"
    },
    {
      "n": 19,
      "type_id": 1,
      "question": "What was the total number of cups of tea and coffee sold?",
      "answer0": "30",
      "answer1": "60",
      "answer2": "90",
      "answer3": "100",
      "correct_answer": 2,
      "skill_id": 104,
      "difficulty_id": 1,
      "explanation": "From the bar graph: tea = 30 cups, coffee = 60 cups. Total = 30 + 60 = 90 cups.",
      "hints": ["Read the height of the tea bar and the coffee bar.", "Add the two values."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q19",
      "image_needed": true,
      "image_options": false,
      "image_file": "q19.png",
      "image_page": 9,
      "image_bbox": [0.18, 0.15, 0.82, 0.42],
      "image_loc": "top of page, bar graph 'Number of cups sold' with bars for Tea, Soda, Milk, Coffee, Juice (shared by Q19 and Q20)",
      "notes": "Key: option 3 (1-based) = index 2 (90). Tea=30, Coffee=60."
    },
    {
      "n": 20,
      "type_id": 1,
      "question": "How many more cups of coffee than cups of milk were sold?",
      "answer0": "30",
      "answer1": "40",
      "answer2": "60",
      "answer3": "80",
      "correct_answer": 1,
      "skill_id": 104,
      "difficulty_id": 1,
      "explanation": "From the bar graph: coffee = 60 cups, milk = 20 cups. Difference = 60 - 20 = 40 cups.",
      "hints": ["Read the coffee bar and the milk bar.", "Subtract the milk value from the coffee value."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q20",
      "image_needed": true,
      "image_options": false,
      "image_file": "q20.png",
      "image_page": 9,
      "image_bbox": [0.18, 0.15, 0.82, 0.42],
      "image_loc": "top of page, bar graph 'Number of cups sold' with bars for Tea, Soda, Milk, Coffee, Juice (same graph as Q19)",
      "notes": "Key: option 2 (1-based) = index 1 (40). Coffee=60, Milk=20."
    },
    {
      "n": 21,
      "type_id": 2,
      "question": "Arrange these numbers from the smallest to the greatest.<br>5604 , 5064 , 5640<br>[?] , [?] , [?]",
      "answer0": "5064",
      "answer1": "5604",
      "answer2": "5640",
      "answer3": null,
      "correct_answer": null,
      "skill_id": 107,
      "difficulty_id": 1,
      "explanation": "Compare the numbers by place value. 5064 (thousands 5, hundreds 0), 5604 (hundreds 6), 5640 (hundreds 6, tens 4). Smallest to greatest: 5064, 5604, 5640.",
      "hints": ["Compare the hundreds digit first.", "5064 has 0 hundreds, so it is smallest."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q21",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 5064, 5504, 5640 — the printed key contains a typo (5504 is not one of the given numbers). Correct ordering of the given numbers 5604/5064/5640 is 5064, 5604, 5640."
    },
    {
      "n": 22,
      "type_id": 2,
      "question": "Some factors of 18 are 1, 2, 3 and 18. What are the other two factors of 18?<br>[?] and [?]",
      "answer0": "6",
      "answer1": "9",
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 111,
      "difficulty_id": 1,
      "explanation": "The factors of 18 are 1, 2, 3, 6, 9, 18. The ones not listed are 6 and 9.",
      "hints": ["List all numbers that divide 18 exactly.", "Pair each factor with its partner: 2 x 9, 3 x 6."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q22",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 6 and 9"
    },
    {
      "n": 23,
      "type_id": 2,
      "question": "Write $$3\\frac{4}{5}$$ as an improper fraction.<br>[?]",
      "answer0": "19/5",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 119,
      "difficulty_id": 1,
      "explanation": "Multiply the whole number by the denominator and add the numerator: 3 x 5 + 4 = 19. So 3 4/5 = 19/5.",
      "hints": ["Whole number x denominator + numerator gives the new numerator.", "3 x 5 + 4 = 19; keep the denominator 5."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q23",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 19/5"
    },
    {
      "n": 24,
      "type_id": 2,
      "question": "$$\\frac{1}{4} + \\frac{5}{8}$$ = [?]",
      "answer0": "7/8",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 121,
      "difficulty_id": 1,
      "explanation": "Make the denominators the same: 1/4 = 2/8. Then 2/8 + 5/8 = 7/8.",
      "hints": ["Change 1/4 to eighths.", "1/4 = 2/8."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q24",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 7/8"
    },
    {
      "n": 25,
      "type_id": 2,
      "question": "$$1 - \\frac{1}{10} - \\frac{1}{5}$$ = [?]",
      "answer0": "7/10",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 121,
      "difficulty_id": 2,
      "explanation": "Convert to tenths: 1 = 10/10, 1/5 = 2/10. Then 10/10 - 1/10 - 2/10 = 7/10.",
      "hints": ["Write 1 and 1/5 as tenths.", "1 = 10/10, 1/5 = 2/10."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q25",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 7/10"
    },
    {
      "n": 26,
      "type_id": 2,
      "question": "3.06 + 5 = [?]",
      "answer0": "8.06",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 129,
      "difficulty_id": 1,
      "explanation": "Add the whole numbers: 3.06 + 5 = 8.06.",
      "hints": ["Add 5 to the whole-number part.", "The decimal part stays as .06."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q26",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 8.06"
    },
    {
      "n": 27,
      "type_id": 2,
      "question": "Find the value of $$7.64 \\times 4$$.<br>[?]",
      "answer0": "30.56",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 130,
      "difficulty_id": 1,
      "explanation": "Multiply: 7.64 x 4 = 30.56.",
      "hints": ["Multiply 764 x 4 = 3056, then place the decimal point.", "There are 2 decimal places in 7.64, so the answer has 2 decimal places."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q27",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: 30.56"
    },
    {
      "n": 28,
      "type_id": 2,
      "question": "Measure and write down the size of $$\\angle x$$.<br>[?]",
      "answer0": "45",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 140,
      "difficulty_id": 1,
      "explanation": "Using a protractor to measure the marked angle x gives 45 degrees.",
      "hints": ["Place the protractor centre on the vertex of the angle.", "Read from the 0 line along one arm to the other arm."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q28",
      "image_needed": true,
      "image_options": false,
      "image_file": "q28.png",
      "image_page": 14,
      "image_bbox": [0.26, 0.36, 0.56, 0.52],
      "image_loc": "left-middle of page, an angle drawn with a horizontal arm and a slanted arm, marked x at the vertex",
      "notes": "Key: 45 degrees. Answer stored plain (45); unit is degrees."
    },
    {
      "n": 29,
      "type_id": 2,
      "question": "EFGH is a rectangle. Find $$\\angle b$$.<br>[?]",
      "answer0": "49",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 230,
      "difficulty_id": 3,
      "explanation": "At corner F the right angle of the rectangle is 90 degrees. It is split into 28 degrees + angle b + 13 degrees. So angle b = 90 - 28 - 13 = 49 degrees.",
      "hints": ["The angle at corner F of a rectangle is 90 degrees.", "The three angles at F add up to 90 degrees."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q29",
      "image_needed": true,
      "image_options": false,
      "image_file": "q29.png",
      "image_page": 14,
      "image_bbox": [0.22, 0.60, 0.62, 0.82],
      "image_loc": "lower-middle of page, rectangle EFGH with lines from F splitting corner F into angles 28 degrees, b and 13 degrees",
      "notes": "Key: 49 degrees. Answer stored plain (49); unit is degrees."
    },
    {
      "n": 30,
      "type_id": 2,
      "question": "The perimeter of a rectangular table is 420 cm. Its breadth is 75 cm. Find its length.<br>[?]",
      "answer0": "135",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 136,
      "difficulty_id": 2,
      "explanation": "Half the perimeter = length + breadth = 420 div 2 = 210 cm. Length = 210 - 75 = 135 cm.",
      "hints": ["Perimeter = 2 x (length + breadth), so length + breadth = perimeter div 2.", "Subtract the breadth from half the perimeter."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q30",
      "image_needed": true,
      "image_options": false,
      "image_file": "q30.png",
      "image_page": 15,
      "image_bbox": [0.26, 0.15, 0.62, 0.27],
      "image_loc": "top of page, rectangle with length marked ? on top and breadth 75 cm on the right",
      "notes": "Key: 135 cm. Answer stored plain (135); unit is cm."
    },
    {
      "n": 31,
      "type_id": 2,
      "question": "The pie chart shows the amounts of donations collected by four classes. All four classes collected a total of $480. What was the amount collected by class 6D?<br>$[?]",
      "answer0": "72",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 236,
      "difficulty_id": 3,
      "explanation": "6A is a right angle (one quarter of the circle), so 6A = 480 div 4 = $120. Total = $480, with 6C = $163 and 6B = $125. 6D = 480 - 120 - 163 - 125 = $72.",
      "hints": ["The right-angle sector (6A) is one quarter of the total.", "Subtract the three known amounts from $480."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q31",
      "image_needed": true,
      "image_options": false,
      "image_file": "q31.png",
      "image_page": 15,
      "image_bbox": [0.28, 0.52, 0.62, 0.78],
      "image_loc": "lower-middle of page, pie chart titled 'Total amount of money collected' with sectors 6D, 6A, 6B ($125), 6C ($163); right-angle mark at centre for 6A",
      "notes": "Key: $72. Answer stored plain (72); unit is dollars."
    },
    {
      "n": 32,
      "type_id": 2,
      "question": "Mr Lim has $3080. He has 7 times as much money as Mr Ng. How much money does Mr Ng have?<br>$[?]",
      "answer0": "440",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 118,
      "difficulty_id": 1,
      "explanation": "Mr Ng has 7 times less, so Mr Ng = $3080 div 7 = $440.",
      "hints": ["If Mr Lim has 7 times as much, divide by 7 to find Mr Ng's amount.", "3080 div 7 = 440."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q32",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: $440. Answer stored plain (440); unit is dollars."
    },
    {
      "n": 33,
      "type_id": 2,
      "question": "There are 872 pears and peaches in a box. $$\\frac{3}{8}$$ of them are pears. How many peaches are there?<br>[?]",
      "answer0": "545",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 120,
      "difficulty_id": 2,
      "explanation": "Peaches are the remaining fraction: 1 - 3/8 = 5/8. Number of peaches = 5/8 x 872 = 5 x 109 = 545.",
      "hints": ["Find the fraction that are peaches: 1 - 3/8.", "5/8 of 872 = (872 div 8) x 5."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q33",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Printed answer key prints '$45' for Q33, which is wrong (it carries over the $ formatting and digits from Q32/Q34). Correct value = 5/8 of 872 = 545 peaches. Stored corrected answer 545."
    },
    {
      "n": 34,
      "type_id": 2,
      "question": "Mrs Tay bought a dress and 2 skirts for $250. The dress cost $65.50 more than a skirt. What was the cost of 1 skirt?<br>$[?]",
      "answer0": "61.50",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 131,
      "difficulty_id": 3,
      "explanation": "Let 1 skirt = 1 unit. Dress = 1 unit + $65.50. Total = 3 units + $65.50 = $250, so 3 units = $184.50, 1 unit = $61.50. One skirt costs $61.50.",
      "hints": ["Express the dress in terms of one skirt plus $65.50.", "Subtract $65.50 from $250, then divide by 3."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q34",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key: $61.50. Answer stored plain (61.50); unit is dollars."
    },
    {
      "n": 35,
      "type_id": 2,
      "question": "The figure is made up of 2 identical rectangles. The total area of the figure is 72 cm². Find the length of one rectangle.<br>[?]",
      "answer0": "9",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 136,
      "difficulty_id": 2,
      "explanation": "Two identical rectangles have total area 72 cm squared, so one rectangle = 36 cm squared. The breadth is 4 cm (given), so length = 36 div 4 = 9 cm.",
      "hints": ["Area of one rectangle = total area div 2.", "Length = area div breadth (breadth is 4 cm)."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q35",
      "image_needed": true,
      "image_options": false,
      "image_file": "q35.png",
      "image_page": 17,
      "image_bbox": [0.18, 0.49, 0.44, 0.78],
      "image_loc": "left side of page, L-shape of two identical rectangles: one upright (4 cm wide) and one horizontal (length marked ?)",
      "notes": "Key: 9 cm. Answer stored plain (9); unit is cm."
    },
    {
      "n": 36,
      "type_id": 2,
      "question": "The figure is made up of square A and 2 identical rectangles, X and Y. The area of the square is 64 cm². Find the perimeter of the figure.<br>[?]",
      "answer0": "54",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 138,
      "difficulty_id": 3,
      "explanation": "Square A has area 64 cm squared, so its side = 8 cm. The top span 11 cm = side of A (8) + width of X, so X width = 3 cm, X length = 8 cm. Rectangle Y is identical (3 cm by 8 cm). Tracing the outline of the figure gives a total perimeter of 54 cm.",
      "hints": ["Side of square A = square root of 64 = 8 cm.", "The 11 cm spans square A plus rectangle X; trace every outer edge."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q36",
      "image_needed": true,
      "image_options": false,
      "image_file": "q36.png",
      "image_page": 18,
      "image_bbox": [0.22, 0.18, 0.62, 0.34],
      "image_loc": "upper-middle of page, square A in the centre with rectangle X on the right and rectangle Y attached lower-left; 11 cm spanning A and X across the top",
      "notes": "Key: 54 cm. Answer stored plain (54); unit is cm."
    },
    {
      "n": 37,
      "type_id": 0,
      "question": "The figure shows a line WX. Using a protractor, construct an angle such that $$\\angle WXY = 135°$$. Mark and label the angle.",
      "answer0": null,
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 140,
      "difficulty_id": 2,
      "explanation": "Place the protractor centre at X, measure 135 degrees from line XW, and draw ray XY. The constructed angle WXY = 135 degrees.",
      "hints": ["Centre the protractor on X with 0 along XW.", "Mark 135 degrees and draw the ray to point Y."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q37",
      "image_needed": true,
      "image_options": false,
      "image_file": "q37.png",
      "image_page": 18,
      "image_bbox": [0.18, 0.68, 0.52, 0.80],
      "image_loc": "lower-middle of page, a single slanted line segment with W at upper-left and X at lower-right",
      "notes": "Interactive construct-and-draw task (no value answer) — type_id 0, skipped on insert. Answer = draw ray XY so angle WXY = 135 degrees."
    },
    {
      "n": 38,
      "type_id": 0,
      "question": "Line AB and Line BC are drawn in the grid. Complete and label the rectangle ABCD by drawing 2 more lines.",
      "answer0": null,
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 143,
      "difficulty_id": 2,
      "explanation": "ABC forms two sides of a rectangle (a right angle at B). Draw AD parallel and equal to BC, and DC parallel and equal to AB, to complete rectangle ABCD; label the new vertex D.",
      "hints": ["Opposite sides of a rectangle are equal and parallel.", "Draw AD equal/parallel to BC and DC equal/parallel to AB; D is the fourth corner."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q38",
      "image_needed": true,
      "image_options": false,
      "image_file": "q38.png",
      "image_page": 19,
      "image_bbox": [0.16, 0.16, 0.70, 0.38],
      "image_loc": "upper-left of page, square grid with line AB and line BC drawn (A upper-left, B at bottom, C to the right)",
      "notes": "Interactive draw-on-grid task (no value answer) — type_id 0, skipped on insert. Answer = complete rectangle ABCD; new vertex D is up-left of C."
    },
    {
      "n": 39,
      "type_id": 2,
      "question": "In which month was the sale of the number of toys four times the sale of the number of toys in January?<br>[?]",
      "answer0": "May",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 147,
      "difficulty_id": 2,
      "explanation": "January sales = 40 toys. Four times that = 160 toys. From the line graph, May had 160 toys. So the answer is May.",
      "hints": ["Read January's value first (40), then find 4 x 40 = 160.", "Find which month's point is at 160."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q39",
      "image_needed": true,
      "image_options": false,
      "image_file": "q39.png",
      "image_page": 20,
      "image_bbox": [0.18, 0.18, 0.78, 0.42],
      "image_loc": "top of page, line graph 'Number of toys sold by a toy store' Jan-May (Jan 40, Feb 120, Mar 70, Apr 190, May 160); shared with Q40",
      "notes": "Key: May. Word answer but a single fixed value from the graph; kept as FIB per spec (definite value)."
    },
    {
      "n": 40,
      "type_id": 2,
      "question": "What was the difference between the greatest and the least number of toys sold in a month?<br>[?]",
      "answer0": "150",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 147,
      "difficulty_id": 2,
      "explanation": "Greatest = April = 190 toys; least = January = 40 toys. Difference = 190 - 40 = 150 toys.",
      "hints": ["Find the highest point and the lowest point on the line graph.", "Subtract the least from the greatest."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q40",
      "image_needed": true,
      "image_options": false,
      "image_file": "q40.png",
      "image_page": 20,
      "image_bbox": [0.18, 0.18, 0.78, 0.42],
      "image_loc": "top of page, same line graph as Q39 (Jan 40, Feb 120, Mar 70, Apr 190, May 160)",
      "notes": "Key: 150. Greatest 190 (April), least 40 (January)."
    },
    {
      "n": 41,
      "type_id": 2,
      "question": "Johnson and Steven have 1200 sweets altogether. Johnson has 5 times as many sweets as Steven. How many sweets must Johnson give to Steven so that they have the same number of sweets?<br>[?]",
      "answer0": "400",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 118,
      "difficulty_id": 3,
      "explanation": "Total = 6 units = 1200, so 1 unit = 200. Steven = 200, Johnson = 1000. To be equal each must have 600. Johnson must give Steven 1000 - 600 = 400 sweets. (Equivalently, give 2 units = 400.)",
      "hints": ["Johnson 5 units + Steven 1 unit = 6 units = 1200.", "Equal share is half of the total; find how much Johnson must give away."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q41",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key working: 6u=1200, 1u=200, give 2u=400. Answer 400 sweets."
    },
    {
      "n": 42,
      "type_id": 2,
      "question": "In a clothing donation drive, Classes 4A, 4B and 4C collected 3445 kg of clothes in total. Class 4A collected 123 kg less than the combined collection of classes 4B and 4C. Class 4C collected 3 times the amount collected by class 4B. What was the amount of clothes collected by class 4B?<br>[?]",
      "answer0": "446",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 118,
      "difficulty_id": 3,
      "explanation": "Let 4B = 1 unit, 4C = 3 units, so 4B+4C = 4 units. 4A = 4 units - 123. Total = (4 units) + (4 units - 123) = 8 units - 123 = 3445. So 8 units = 3568, 1 unit = 446. Class 4B collected 446 kg.",
      "hints": ["Write 4C as 3 units and 4A in terms of units minus 123.", "Add all three to 8 units - 123 = 3445."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q42",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key working: 8u = 3445+123 = 3568, 1u = 446 kg."
    },
    {
      "n": 43,
      "type_id": 2,
      "question": "Joan had some money. She spent $$\\frac{2}{3}$$ of it on a dress and $$\\frac{1}{4}$$ of it on a doll. She had $27 left. How much more money did she spend on the dress than on the doll?<br>$[?]",
      "answer0": "135",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 122,
      "difficulty_id": 3,
      "explanation": "Spent = 2/3 + 1/4 = 8/12 + 3/12 = 11/12. Left = 1/12 = $27, so the whole = $324. Dress = 8/12 = $216, doll = 3/12 = $81. Difference = 216 - 81 = $135.",
      "hints": ["Add the spent fractions to find the leftover fraction.", "1/12 = $27, so scale up to find the dress and doll amounts."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q43",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key working: 1/12 -> $27; dress 8u=$216, doll 3u=$81; difference $135."
    },
    {
      "n": 44,
      "type_id": 2,
      "question": "Lisa had 10 kg of grapes more than Zara. When Lisa gave away 1.5 kg of grapes and Zara gave away 0.5 kg of grapes, Lisa still had 4 times as much grapes as Zara. How many kilograms of grapes did Zara have at first?<br>[?]",
      "answer0": "3.5",
      "answer1": null,
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 131,
      "difficulty_id": 3,
      "explanation": "After giving away, the difference between Lisa and Zara = 10 - 1.5 + 0.5 = 9 kg. This difference is 4 units - 1 unit = 3 units = 9 kg, so 1 unit = 3 kg (Zara's amount after giving away). Zara at first = 3 + 0.5 = 3.5 kg.",
      "hints": ["Find the new difference after both give grapes away.", "The difference equals 3 units; Zara's start = her after-amount + 0.5 kg."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q44",
      "image_needed": false,
      "image_options": false,
      "image_file": null,
      "notes": "Key working: 3u = 10-1.5+0.5 = 9, 1u = 3, Zara first = 3+0.5 = 3.5 kg."
    },
    {
      "n": 45,
      "type_id": 2,
      "question": "The figure is made up of 5 identical rectangles. The perimeter of each rectangle is 56 cm.<br>a) Find the length of WZ.<br>b) Find the area of the figure.<br>WZ = [?] cm<br>Area = [?] cm²",
      "answer0": "35",
      "answer1": "735",
      "answer2": null,
      "answer3": null,
      "correct_answer": null,
      "skill_id": 138,
      "difficulty_id": 3,
      "explanation": "Each rectangle: length = 3 x breadth (3 small rectangles stand across the width of one). Perimeter = 2(length + breadth) = 8 breadths = 56, so 1 breadth = 7 cm and length = 21 cm. (a) WZ = 5 breadths = 5 x 7 = 35 cm. (b) Area of 1 rectangle = 7 x 21 = 147 cm squared; area of figure = 5 x 147 = 735 cm squared.",
      "hints": ["From the arrangement, the length is 3 times the breadth; use the perimeter to find the breadth.", "WZ spans 5 breadths; the whole figure is 5 rectangles."],
      "source": "St Hilda 2025 P4 End-of-Year Exam Q45",
      "image_needed": true,
      "image_options": false,
      "image_file": "q45.png",
      "image_page": 25,
      "image_bbox": [0.18, 0.18, 0.42, 0.42],
      "image_loc": "left side of page, tall figure WXYZ made of 5 identical rectangles (three standing side-by-side in the middle, one across top, one across bottom); WZ is the left side marked ?",
      "notes": "Key: (a) WZ = 35 cm; (b) area = 735 cm squared. Two real answer blanks (answer0=35, answer1=735)."
    }
  ]
}