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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 4 and 10?

    4 · 10 · Lowest common multiple (LCM)

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

    15 · 21 · Lowest common multiple (LCM)

  3. 3. What is the lowest common multiple (LCM) of 20 and 70?

    20 · 70 · Lowest common multiple (LCM)

  4. 4. What is the lowest common multiple (LCM) of 10 and 35?

    10 · 35 · Lowest common multiple (LCM)

  5. 5. What is the lowest common multiple (LCM) of 16 and 56?

    16 · 56 · Lowest common multiple (LCM)

  6. 6. What is the lowest common multiple (LCM) of 15 and 20?

    15 · 20 · Lowest common multiple (LCM)

  7. 7. What is the lowest common multiple (LCM) of 21 and 28?

    21 · 28 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 32 and 56?

    32 · 56 · Lowest common multiple (LCM)

  9. 9. What is the lowest common multiple (LCM) of 12 and 30?

    12 · 30 · Lowest common multiple (LCM)

  10. 10. What is the lowest common multiple (LCM) of 36 and 48?

    36 · 48 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 35 and 42?

    35 · 42 · Lowest common multiple (LCM)

  12. 12. What is the lowest common multiple (LCM) of 28 and 49?

    28 · 49 · Lowest common multiple (LCM)
12 questions · Seed 45 · 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 4 and 10?

    20

    The highest common factor of 4 and 10 is 2, so LCM = (4 × 10) ÷ 2 = 20.

  2. 2. 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.

  3. 3. What is the lowest common multiple (LCM) of 20 and 70?

    140

    The highest common factor of 20 and 70 is 10, so LCM = (20 × 70) ÷ 10 = 140.

  4. 4. What is the lowest common multiple (LCM) of 10 and 35?

    70

    The highest common factor of 10 and 35 is 5, so LCM = (10 × 35) ÷ 5 = 70.

  5. 5. What is the lowest common multiple (LCM) of 16 and 56?

    112

    The highest common factor of 16 and 56 is 8, so LCM = (16 × 56) ÷ 8 = 112.

  6. 6. What is the lowest common multiple (LCM) of 15 and 20?

    60

    The highest common factor of 15 and 20 is 5, so LCM = (15 × 20) ÷ 5 = 60.

  7. 7. What is the lowest common multiple (LCM) of 21 and 28?

    84

    The highest common factor of 21 and 28 is 7, so LCM = (21 × 28) ÷ 7 = 84.

  8. 8. What is the lowest common multiple (LCM) of 32 and 56?

    224

    The highest common factor of 32 and 56 is 8, so LCM = (32 × 56) ÷ 8 = 224.

  9. 9. What is the lowest common multiple (LCM) of 12 and 30?

    60

    The highest common factor of 12 and 30 is 6, so LCM = (12 × 30) ÷ 6 = 60.

  10. 10. What is the lowest common multiple (LCM) of 36 and 48?

    144

    The highest common factor of 36 and 48 is 12, so LCM = (36 × 48) ÷ 12 = 144.

  11. 11. What is the lowest common multiple (LCM) of 35 and 42?

    210

    The highest common factor of 35 and 42 is 7, so LCM = (35 × 42) ÷ 7 = 210.

  12. 12. What is the lowest common multiple (LCM) of 28 and 49?

    196

    The highest common factor of 28 and 49 is 7, so LCM = (28 × 49) ÷ 7 = 196.

12 questions · Seed 45 · 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 4 and 10?

    4 · 10 · Lowest common multiple (LCM)

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

    15 · 21 · Lowest common multiple (LCM)

  3. 3. What is the lowest common multiple (LCM) of 20 and 70?

    20 · 70 · Lowest common multiple (LCM)

  4. 4. What is the lowest common multiple (LCM) of 10 and 35?

    10 · 35 · Lowest common multiple (LCM)

  5. 5. What is the lowest common multiple (LCM) of 16 and 56?

    16 · 56 · Lowest common multiple (LCM)

  6. 6. What is the lowest common multiple (LCM) of 15 and 20?

    15 · 20 · Lowest common multiple (LCM)

  7. 7. What is the lowest common multiple (LCM) of 21 and 28?

    21 · 28 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 32 and 56?

    32 · 56 · Lowest common multiple (LCM)

  9. 9. What is the lowest common multiple (LCM) of 12 and 30?

    12 · 30 · Lowest common multiple (LCM)

  10. 10. What is the lowest common multiple (LCM) of 36 and 48?

    36 · 48 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 35 and 42?

    35 · 42 · Lowest common multiple (LCM)

  12. 12. What is the lowest common multiple (LCM) of 28 and 49?

    28 · 49 · Lowest common multiple (LCM)
12 questions · Seed 45 · 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 4 and 10?

    20

    The highest common factor of 4 and 10 is 2, so LCM = (4 × 10) ÷ 2 = 20.

  2. 2. 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.

  3. 3. What is the lowest common multiple (LCM) of 20 and 70?

    140

    The highest common factor of 20 and 70 is 10, so LCM = (20 × 70) ÷ 10 = 140.

  4. 4. What is the lowest common multiple (LCM) of 10 and 35?

    70

    The highest common factor of 10 and 35 is 5, so LCM = (10 × 35) ÷ 5 = 70.

  5. 5. What is the lowest common multiple (LCM) of 16 and 56?

    112

    The highest common factor of 16 and 56 is 8, so LCM = (16 × 56) ÷ 8 = 112.

  6. 6. What is the lowest common multiple (LCM) of 15 and 20?

    60

    The highest common factor of 15 and 20 is 5, so LCM = (15 × 20) ÷ 5 = 60.

  7. 7. What is the lowest common multiple (LCM) of 21 and 28?

    84

    The highest common factor of 21 and 28 is 7, so LCM = (21 × 28) ÷ 7 = 84.

  8. 8. What is the lowest common multiple (LCM) of 32 and 56?

    224

    The highest common factor of 32 and 56 is 8, so LCM = (32 × 56) ÷ 8 = 224.

  9. 9. What is the lowest common multiple (LCM) of 12 and 30?

    60

    The highest common factor of 12 and 30 is 6, so LCM = (12 × 30) ÷ 6 = 60.

  10. 10. What is the lowest common multiple (LCM) of 36 and 48?

    144

    The highest common factor of 36 and 48 is 12, so LCM = (36 × 48) ÷ 12 = 144.

  11. 11. What is the lowest common multiple (LCM) of 35 and 42?

    210

    The highest common factor of 35 and 42 is 7, so LCM = (35 × 42) ÷ 7 = 210.

  12. 12. What is the lowest common multiple (LCM) of 28 and 49?

    196

    The highest common factor of 28 and 49 is 7, so LCM = (28 × 49) ÷ 7 = 196.

12 questions · Seed 45 · Age guidance, not curriculum certification