{
  "title": "Open numeracy practice: 30 questions",
  "version": "2026-09-10.1",
  "publisher": "Quizverse",
  "authorship": "AI-assisted original draft; no named educator review",
  "license": "CC BY 4.0",
  "licenseUrl": "https://creativecommons.org/licenses/by/4.0/",
  "attribution": "Open numeracy practice: 30 questions — Quizverse, 2026-09-10, CC BY 4.0. AI-assisted draft; indicate your changes.",
  "scope": "General numeracy practice; not aligned to a named examination, grade standard or diagnostic threshold.",
  "review": {
    "educator": null,
    "reviewDate": null,
    "ambiguities": null,
    "pedagogicalErrors": null,
    "status": "educator review pending"
  },
  "questions": [
    {
      "id": 1,
      "module": "Number operations",
      "question": "What is 18 + 27?",
      "answer": 45,
      "unit": "",
      "explanation": "Add tens and ones: 10 + 20 + 8 + 7 = 45.",
      "check": {
        "operation": "sum",
        "values": [
          18,
          27
        ]
      }
    },
    {
      "id": 2,
      "module": "Number operations",
      "question": "What is 64 − 29?",
      "answer": 35,
      "unit": "",
      "explanation": "Subtract 30 to get 34, then add 1 back: 35.",
      "check": {
        "operation": "subtract",
        "values": [
          64,
          29
        ]
      }
    },
    {
      "id": 3,
      "module": "Number operations",
      "question": "What is 7 × 8?",
      "answer": 56,
      "unit": "",
      "explanation": "Seven groups of eight contain 56 objects.",
      "check": {
        "operation": "product",
        "values": [
          7,
          8
        ]
      }
    },
    {
      "id": 4,
      "module": "Number operations",
      "question": "What is 84 ÷ 7?",
      "answer": 12,
      "unit": "",
      "explanation": "Since 7 × 12 = 84, the quotient is 12.",
      "check": {
        "operation": "divide",
        "values": [
          84,
          7
        ]
      }
    },
    {
      "id": 5,
      "module": "Number operations",
      "question": "What is 6 + 3 × 4?",
      "answer": 18,
      "unit": "",
      "explanation": "Multiply first: 3 × 4 = 12. Then 6 + 12 = 18.",
      "check": {
        "operation": "multiplyThenAdd",
        "values": [
          6,
          3,
          4
        ]
      }
    },
    {
      "id": 6,
      "module": "Fractions and decimals",
      "question": "What is 1/2 + 1/4, expressed as a decimal?",
      "answer": 0.75,
      "unit": "",
      "explanation": "Convert to quarters: 2/4 + 1/4 = 3/4 = 0.75.",
      "check": {
        "operation": "sum",
        "values": [
          0.5,
          0.25
        ]
      }
    },
    {
      "id": 7,
      "module": "Fractions and decimals",
      "question": "What is 3/4 − 1/8, expressed as a decimal?",
      "answer": 0.625,
      "unit": "",
      "explanation": "Use eighths: 6/8 − 1/8 = 5/8 = 0.625.",
      "check": {
        "operation": "subtract",
        "values": [
          0.75,
          0.125
        ]
      }
    },
    {
      "id": 8,
      "module": "Fractions and decimals",
      "question": "What is 2/3 of 18?",
      "answer": 12,
      "unit": "",
      "explanation": "Divide 18 into three equal parts of 6; take two parts: 12.",
      "check": {
        "operation": "product",
        "values": [
          0.6666666666666666,
          18
        ]
      }
    },
    {
      "id": 9,
      "module": "Fractions and decimals",
      "question": "What is 0.6 × 0.5?",
      "answer": 0.3,
      "unit": "",
      "explanation": "Six tenths times five tenths is thirty hundredths, or 0.3.",
      "check": {
        "operation": "product",
        "values": [
          0.6,
          0.5
        ]
      }
    },
    {
      "id": 10,
      "module": "Fractions and decimals",
      "question": "What is 1.25 + 0.75?",
      "answer": 2,
      "unit": "",
      "explanation": "125 hundredths plus 75 hundredths is 200 hundredths, or 2.",
      "check": {
        "operation": "sum",
        "values": [
          1.25,
          0.75
        ]
      }
    },
    {
      "id": 11,
      "module": "Percentages and ratios",
      "question": "What is 20% of 150?",
      "answer": 30,
      "unit": "",
      "explanation": "20% is 0.20, and 0.20 × 150 = 30.",
      "check": {
        "operation": "product",
        "values": [
          0.2,
          150
        ]
      }
    },
    {
      "id": 12,
      "module": "Percentages and ratios",
      "question": "An $80 item is discounted by 25%. What is the price before tax?",
      "answer": 60,
      "unit": "USD",
      "explanation": "The discount is 0.25 × 80 = $20. Subtract $20 from $80.",
      "check": {
        "operation": "discount",
        "values": [
          80,
          25
        ]
      }
    },
    {
      "id": 13,
      "module": "Percentages and ratios",
      "question": "A class has 12 girls and 8 boys. What percentage of the 20 students are girls?",
      "answer": 60,
      "unit": "%",
      "explanation": "Divide 12 by 20 and multiply by 100: 60%.",
      "check": {
        "operation": "percent",
        "values": [
          12,
          20
        ]
      }
    },
    {
      "id": 14,
      "module": "Percentages and ratios",
      "question": "Red and blue counters are in the ratio 2:3. There are 25 counters total. How many are red?",
      "answer": 10,
      "unit": "counters",
      "explanation": "There are five equal ratio parts. Each is 25 ÷ 5 = 5; red has two parts.",
      "check": {
        "operation": "ratioShare",
        "values": [
          2,
          3,
          25
        ]
      }
    },
    {
      "id": 15,
      "module": "Percentages and ratios",
      "question": "A value increases from 40 to 50. What is the percentage increase?",
      "answer": 25,
      "unit": "%",
      "explanation": "The increase is 10; divide by the original 40, then multiply by 100.",
      "check": {
        "operation": "increase",
        "values": [
          40,
          50
        ]
      }
    },
    {
      "id": 16,
      "module": "Introductory algebra",
      "question": "Solve x + 7 = 19. What is x?",
      "answer": 12,
      "unit": "",
      "explanation": "Subtract 7 from both sides: x = 12.",
      "check": {
        "operation": "subtract",
        "values": [
          19,
          7
        ]
      }
    },
    {
      "id": 17,
      "module": "Introductory algebra",
      "question": "Solve 4x = 28. What is x?",
      "answer": 7,
      "unit": "",
      "explanation": "Divide both sides by 4: x = 7.",
      "check": {
        "operation": "divide",
        "values": [
          28,
          4
        ]
      }
    },
    {
      "id": 18,
      "module": "Introductory algebra",
      "question": "Solve 2x + 3 = 15. What is x?",
      "answer": 6,
      "unit": "",
      "explanation": "Subtract 3 to get 2x = 12, then divide by 2.",
      "check": {
        "operation": "linear",
        "values": [
          2,
          3,
          15
        ]
      }
    },
    {
      "id": 19,
      "module": "Introductory algebra",
      "question": "Evaluate 3a − 2 when a = 5.",
      "answer": 13,
      "unit": "",
      "explanation": "Substitute 5 for a: 3 × 5 − 2 = 15 − 2 = 13.",
      "check": {
        "operation": "productMinus",
        "values": [
          3,
          5,
          2
        ]
      }
    },
    {
      "id": 20,
      "module": "Introductory algebra",
      "question": "Continue the arithmetic sequence 4, 9, 14, 19. What is the next term?",
      "answer": 24,
      "unit": "",
      "explanation": "An arithmetic sequence uses a constant difference. Add 5 to 19.",
      "check": {
        "operation": "sum",
        "values": [
          19,
          5
        ]
      }
    },
    {
      "id": 21,
      "module": "Measurement and geometry",
      "question": "A rectangle is 8 cm long and 3 cm wide. What is its perimeter?",
      "answer": 22,
      "unit": "cm",
      "explanation": "Perimeter is 2 × (length + width): 2 × (8 + 3) = 22 cm.",
      "check": {
        "operation": "perimeter",
        "values": [
          8,
          3
        ]
      }
    },
    {
      "id": 22,
      "module": "Measurement and geometry",
      "question": "A rectangle is 9 m long and 4 m wide. What is its area?",
      "answer": 36,
      "unit": "m²",
      "explanation": "Area is length × width: 9 × 4 = 36 square metres.",
      "check": {
        "operation": "product",
        "values": [
          9,
          4
        ]
      }
    },
    {
      "id": 23,
      "module": "Measurement and geometry",
      "question": "A triangle has base 10 cm and perpendicular height 6 cm. What is its area?",
      "answer": 30,
      "unit": "cm²",
      "explanation": "Area is one half × base × perpendicular height: 0.5 × 10 × 6 = 30.",
      "check": {
        "operation": "triangle",
        "values": [
          10,
          6
        ]
      }
    },
    {
      "id": 24,
      "module": "Measurement and geometry",
      "question": "A square has perimeter 28 cm. What is the length of one side?",
      "answer": 7,
      "unit": "cm",
      "explanation": "A square has four equal sides. Divide 28 by 4 to obtain 7 cm.",
      "check": {
        "operation": "divide",
        "values": [
          28,
          4
        ]
      }
    },
    {
      "id": 25,
      "module": "Measurement and geometry",
      "question": "How many centimetres are in 2.5 metres?",
      "answer": 250,
      "unit": "cm",
      "explanation": "One metre equals 100 centimetres; multiply 2.5 by 100.",
      "check": {
        "operation": "product",
        "values": [
          2.5,
          100
        ]
      }
    },
    {
      "id": 26,
      "module": "Data and probability",
      "question": "What is the arithmetic mean of 4, 6, 8 and 10?",
      "answer": 7,
      "unit": "",
      "explanation": "The sum is 28. Divide by the four values: 28 ÷ 4 = 7.",
      "check": {
        "operation": "mean",
        "values": [
          4,
          6,
          8,
          10
        ]
      }
    },
    {
      "id": 27,
      "module": "Data and probability",
      "question": "What is the median of 3, 9, 5, 11 and 7?",
      "answer": 7,
      "unit": "",
      "explanation": "Order the values: 3, 5, 7, 9, 11. The middle value is 7.",
      "check": {
        "operation": "median",
        "values": [
          3,
          9,
          5,
          11,
          7
        ]
      }
    },
    {
      "id": 28,
      "module": "Data and probability",
      "question": "What is the range of the values 12, 4, 15 and 9?",
      "answer": 11,
      "unit": "",
      "explanation": "Range is greatest minus least: 15 − 4 = 11.",
      "check": {
        "operation": "range",
        "values": [
          12,
          4,
          15,
          9
        ]
      }
    },
    {
      "id": 29,
      "module": "Data and probability",
      "question": "A fair six-sided die has faces numbered 1 through 6. What is the probability of rolling an even number, as a decimal?",
      "answer": 0.5,
      "unit": "",
      "explanation": "Three of six equally likely faces are even: 2, 4 and 6. Thus 3/6 = 0.5.",
      "check": {
        "operation": "divide",
        "values": [
          3,
          6
        ]
      }
    },
    {
      "id": 30,
      "module": "Data and probability",
      "question": "A bag has 3 red and 7 blue counters. One counter is selected uniformly at random. What is the probability of red, as a decimal?",
      "answer": 0.3,
      "unit": "",
      "explanation": "There are 10 counters and 3 are red. Equal selection probability gives 3/10 = 0.3.",
      "check": {
        "operation": "divide",
        "values": [
          3,
          10
        ]
      }
    }
  ]
}