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MathsAges 13-15

Lowest common multiple (LCM)

Find the lowest common multiple (LCM) shared by two whole numbers. Review suitability for your learners before teaching.

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Age band:Ages 10-12Ages 13-15

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Worksheet StudioPractice pack · Ages 13-15

Lowest common multiple (LCM)

Take your time. Show your thinking.

  1. 1. What is the lowest common multiple (LCM) of 15 and 21?

    15 · 21 · Lowest common multiple (LCM)

  2. 2. What is the lowest common multiple (LCM) of 24 and 36?

    24 · 36 · Lowest common multiple (LCM)

  3. 3. What is the lowest common multiple (LCM) of 24 and 40?

    24 · 40 · Lowest common multiple (LCM)

  4. 4. What is the lowest common multiple (LCM) of 6 and 21?

    6 · 21 · Lowest common multiple (LCM)

  5. 5. What is the lowest common multiple (LCM) of 30 and 70?

    30 · 70 · Lowest common multiple (LCM)

  6. 6. What is the lowest common multiple (LCM) of 30 and 36?

    30 · 36 · Lowest common multiple (LCM)

  7. 7. What is the lowest common multiple (LCM) of 12 and 18?

    12 · 18 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 12 and 16?

    12 · 16 · Lowest common multiple (LCM)

  9. 9. What is the lowest common multiple (LCM) of 6 and 8?

    6 · 8 · Lowest common multiple (LCM)

  10. 10. What is the lowest common multiple (LCM) of 6 and 10?

    6 · 10 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 6 and 14?

    6 · 14 · Lowest common multiple (LCM)

  12. 12. What is the lowest common multiple (LCM) of 14 and 21?

    14 · 21 · Lowest common multiple (LCM)
12 questions · Seed 51 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 13-15

Lowest common multiple (LCM)

Answers and reasoning. Review before teaching.

  1. 1. What is the lowest common multiple (LCM) of 15 and 21?

    105

    The highest common factor of 15 and 21 is 3, so LCM = (15 × 21) ÷ 3 = 105.

  2. 2. What is the lowest common multiple (LCM) of 24 and 36?

    72

    The highest common factor of 24 and 36 is 12, so LCM = (24 × 36) ÷ 12 = 72.

  3. 3. What is the lowest common multiple (LCM) of 24 and 40?

    120

    The highest common factor of 24 and 40 is 8, so LCM = (24 × 40) ÷ 8 = 120.

  4. 4. What is the lowest common multiple (LCM) of 6 and 21?

    42

    The highest common factor of 6 and 21 is 3, so LCM = (6 × 21) ÷ 3 = 42.

  5. 5. What is the lowest common multiple (LCM) of 30 and 70?

    210

    The highest common factor of 30 and 70 is 10, so LCM = (30 × 70) ÷ 10 = 210.

  6. 6. What is the lowest common multiple (LCM) of 30 and 36?

    180

    The highest common factor of 30 and 36 is 6, so LCM = (30 × 36) ÷ 6 = 180.

  7. 7. What is the lowest common multiple (LCM) of 12 and 18?

    36

    The highest common factor of 12 and 18 is 6, so LCM = (12 × 18) ÷ 6 = 36.

  8. 8. What is the lowest common multiple (LCM) of 12 and 16?

    48

    The highest common factor of 12 and 16 is 4, so LCM = (12 × 16) ÷ 4 = 48.

  9. 9. What is the lowest common multiple (LCM) of 6 and 8?

    24

    The highest common factor of 6 and 8 is 2, so LCM = (6 × 8) ÷ 2 = 24.

  10. 10. What is the lowest common multiple (LCM) of 6 and 10?

    30

    The highest common factor of 6 and 10 is 2, so LCM = (6 × 10) ÷ 2 = 30.

  11. 11. What is the lowest common multiple (LCM) of 6 and 14?

    42

    The highest common factor of 6 and 14 is 2, so LCM = (6 × 14) ÷ 2 = 42.

  12. 12. What is the lowest common multiple (LCM) of 14 and 21?

    42

    The highest common factor of 14 and 21 is 7, so LCM = (14 × 21) ÷ 7 = 42.

12 questions · Seed 51 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 13-15

Lowest common multiple (LCM)

Take your time. Show your thinking.

  1. 1. What is the lowest common multiple (LCM) of 15 and 21?

    15 · 21 · Lowest common multiple (LCM)

  2. 2. What is the lowest common multiple (LCM) of 24 and 36?

    24 · 36 · Lowest common multiple (LCM)

  3. 3. What is the lowest common multiple (LCM) of 24 and 40?

    24 · 40 · Lowest common multiple (LCM)

  4. 4. What is the lowest common multiple (LCM) of 6 and 21?

    6 · 21 · Lowest common multiple (LCM)

  5. 5. What is the lowest common multiple (LCM) of 30 and 70?

    30 · 70 · Lowest common multiple (LCM)

  6. 6. What is the lowest common multiple (LCM) of 30 and 36?

    30 · 36 · Lowest common multiple (LCM)

  7. 7. What is the lowest common multiple (LCM) of 12 and 18?

    12 · 18 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 12 and 16?

    12 · 16 · Lowest common multiple (LCM)

  9. 9. What is the lowest common multiple (LCM) of 6 and 8?

    6 · 8 · Lowest common multiple (LCM)

  10. 10. What is the lowest common multiple (LCM) of 6 and 10?

    6 · 10 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 6 and 14?

    6 · 14 · Lowest common multiple (LCM)

  12. 12. What is the lowest common multiple (LCM) of 14 and 21?

    14 · 21 · Lowest common multiple (LCM)
12 questions · Seed 51 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 13-15

Lowest common multiple (LCM)

Answers and reasoning. Review before teaching.

  1. 1. What is the lowest common multiple (LCM) of 15 and 21?

    105

    The highest common factor of 15 and 21 is 3, so LCM = (15 × 21) ÷ 3 = 105.

  2. 2. What is the lowest common multiple (LCM) of 24 and 36?

    72

    The highest common factor of 24 and 36 is 12, so LCM = (24 × 36) ÷ 12 = 72.

  3. 3. What is the lowest common multiple (LCM) of 24 and 40?

    120

    The highest common factor of 24 and 40 is 8, so LCM = (24 × 40) ÷ 8 = 120.

  4. 4. What is the lowest common multiple (LCM) of 6 and 21?

    42

    The highest common factor of 6 and 21 is 3, so LCM = (6 × 21) ÷ 3 = 42.

  5. 5. What is the lowest common multiple (LCM) of 30 and 70?

    210

    The highest common factor of 30 and 70 is 10, so LCM = (30 × 70) ÷ 10 = 210.

  6. 6. What is the lowest common multiple (LCM) of 30 and 36?

    180

    The highest common factor of 30 and 36 is 6, so LCM = (30 × 36) ÷ 6 = 180.

  7. 7. What is the lowest common multiple (LCM) of 12 and 18?

    36

    The highest common factor of 12 and 18 is 6, so LCM = (12 × 18) ÷ 6 = 36.

  8. 8. What is the lowest common multiple (LCM) of 12 and 16?

    48

    The highest common factor of 12 and 16 is 4, so LCM = (12 × 16) ÷ 4 = 48.

  9. 9. What is the lowest common multiple (LCM) of 6 and 8?

    24

    The highest common factor of 6 and 8 is 2, so LCM = (6 × 8) ÷ 2 = 24.

  10. 10. What is the lowest common multiple (LCM) of 6 and 10?

    30

    The highest common factor of 6 and 10 is 2, so LCM = (6 × 10) ÷ 2 = 30.

  11. 11. What is the lowest common multiple (LCM) of 6 and 14?

    42

    The highest common factor of 6 and 14 is 2, so LCM = (6 × 14) ÷ 2 = 42.

  12. 12. What is the lowest common multiple (LCM) of 14 and 21?

    42

    The highest common factor of 14 and 21 is 7, so LCM = (14 × 21) ÷ 7 = 42.

12 questions · Seed 51 · Age guidance, not curriculum certification