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MathsAges 10-12

Highest common factor (HCF)

Find the highest common factor (HCF) shared by two whole numbers. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 10-12

Highest common factor (HCF)

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  1. 1. What is the highest common factor (HCF) of 12 and 15?

    12 · 15 · Highest common factor (HCF)
  2. 2. What is the highest common factor (HCF) of 15 and 18?

    15 · 18 · Highest common factor (HCF)
  3. 3. What is the highest common factor (HCF) of 16 and 40?

    16 · 40 · Highest common factor (HCF)
  4. 4. What is the highest common factor (HCF) of 9 and 12?

    9 · 12 · Highest common factor (HCF)
  5. 5. What is the highest common factor (HCF) of 16 and 20?

    16 · 20 · Highest common factor (HCF)
  6. 6. What is the highest common factor (HCF) of 39 and 52?

    39 · 52 · Highest common factor (HCF)
  7. 7. What is the highest common factor (HCF) of 20 and 25?

    20 · 25 · Highest common factor (HCF)
  8. 8. What is the highest common factor (HCF) of 6 and 8?

    6 · 8 · Highest common factor (HCF)
  9. 9. What is the highest common factor (HCF) of 25 and 35?

    25 · 35 · Highest common factor (HCF)
  10. 10. What is the highest common factor (HCF) of 18 and 30?

    18 · 30 · Highest common factor (HCF)
  11. 11. What is the highest common factor (HCF) of 24 and 32?

    24 · 32 · Highest common factor (HCF)
  12. 12. What is the highest common factor (HCF) of 28 and 42?

    28 · 42 · Highest common factor (HCF)
12 questions · Seed 42 · Age guidance, not curriculum certification
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Worksheet StudioAnswer key · Ages 10-12

Highest common factor (HCF)

Answers and reasoning. Review before teaching.

  1. 1. What is the highest common factor (HCF) of 12 and 15?

    3

    12 = 4 × 3 and 15 = 5 × 3. Since 4 and 5 share no common factor greater than 1, the HCF is 3.

  2. 2. What is the highest common factor (HCF) of 15 and 18?

    3

    15 = 5 × 3 and 18 = 6 × 3. Since 5 and 6 share no common factor greater than 1, the HCF is 3.

  3. 3. What is the highest common factor (HCF) of 16 and 40?

    8

    16 = 2 × 8 and 40 = 5 × 8. Since 2 and 5 share no common factor greater than 1, the HCF is 8.

  4. 4. What is the highest common factor (HCF) of 9 and 12?

    3

    9 = 3 × 3 and 12 = 4 × 3. Since 3 and 4 share no common factor greater than 1, the HCF is 3.

  5. 5. What is the highest common factor (HCF) of 16 and 20?

    4

    16 = 4 × 4 and 20 = 5 × 4. Since 4 and 5 share no common factor greater than 1, the HCF is 4.

  6. 6. What is the highest common factor (HCF) of 39 and 52?

    13

    39 = 3 × 13 and 52 = 4 × 13. Since 3 and 4 share no common factor greater than 1, the HCF is 13.

  7. 7. What is the highest common factor (HCF) of 20 and 25?

    5

    20 = 4 × 5 and 25 = 5 × 5. Since 4 and 5 share no common factor greater than 1, the HCF is 5.

  8. 8. What is the highest common factor (HCF) of 6 and 8?

    2

    6 = 3 × 2 and 8 = 4 × 2. Since 3 and 4 share no common factor greater than 1, the HCF is 2.

  9. 9. What is the highest common factor (HCF) of 25 and 35?

    5

    25 = 5 × 5 and 35 = 7 × 5. Since 5 and 7 share no common factor greater than 1, the HCF is 5.

  10. 10. What is the highest common factor (HCF) of 18 and 30?

    6

    18 = 3 × 6 and 30 = 5 × 6. Since 3 and 5 share no common factor greater than 1, the HCF is 6.

  11. 11. What is the highest common factor (HCF) of 24 and 32?

    8

    24 = 3 × 8 and 32 = 4 × 8. Since 3 and 4 share no common factor greater than 1, the HCF is 8.

  12. 12. What is the highest common factor (HCF) of 28 and 42?

    14

    28 = 2 × 14 and 42 = 3 × 14. Since 2 and 3 share no common factor greater than 1, the HCF is 14.

12 questions · Seed 42 · Age guidance, not curriculum certification