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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 12 and 42?

    12 · 42 · Lowest common multiple (LCM)

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

    21 · 28 · Lowest common multiple (LCM)

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

    12 · 18 · Lowest common multiple (LCM)

  4. 4. What is the lowest common multiple (LCM) of 33 and 55?

    33 · 55 · Lowest common multiple (LCM)

  5. 5. What is the lowest common multiple (LCM) of 8 and 10?

    8 · 10 · Lowest common multiple (LCM)

  6. 6. What is the lowest common multiple (LCM) of 28 and 35?

    28 · 35 · Lowest common multiple (LCM)

  7. 7. What is the lowest common multiple (LCM) of 55 and 77?

    55 · 77 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 35 and 49?

    35 · 49 · Lowest common multiple (LCM)

  9. 9. What is the lowest common multiple (LCM) of 44 and 77?

    44 · 77 · Lowest common multiple (LCM)

  10. 10. What is the lowest common multiple (LCM) of 36 and 45?

    36 · 45 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 30 and 42?

    30 · 42 · Lowest common multiple (LCM)

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

    6 · 10 · Lowest common multiple (LCM)
12 questions · Seed 61 · 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 12 and 42?

    84

    The highest common factor of 12 and 42 is 6, so LCM = (12 × 42) ÷ 6 = 84.

  2. 2. 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.

  3. 3. 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.

  4. 4. What is the lowest common multiple (LCM) of 33 and 55?

    165

    The highest common factor of 33 and 55 is 11, so LCM = (33 × 55) ÷ 11 = 165.

  5. 5. What is the lowest common multiple (LCM) of 8 and 10?

    40

    The highest common factor of 8 and 10 is 2, so LCM = (8 × 10) ÷ 2 = 40.

  6. 6. What is the lowest common multiple (LCM) of 28 and 35?

    140

    The highest common factor of 28 and 35 is 7, so LCM = (28 × 35) ÷ 7 = 140.

  7. 7. What is the lowest common multiple (LCM) of 55 and 77?

    385

    The highest common factor of 55 and 77 is 11, so LCM = (55 × 77) ÷ 11 = 385.

  8. 8. What is the lowest common multiple (LCM) of 35 and 49?

    245

    The highest common factor of 35 and 49 is 7, so LCM = (35 × 49) ÷ 7 = 245.

  9. 9. What is the lowest common multiple (LCM) of 44 and 77?

    308

    The highest common factor of 44 and 77 is 11, so LCM = (44 × 77) ÷ 11 = 308.

  10. 10. What is the lowest common multiple (LCM) of 36 and 45?

    180

    The highest common factor of 36 and 45 is 9, so LCM = (36 × 45) ÷ 9 = 180.

  11. 11. What is the lowest common multiple (LCM) of 30 and 42?

    210

    The highest common factor of 30 and 42 is 6, so LCM = (30 × 42) ÷ 6 = 210.

  12. 12. 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.

12 questions · Seed 61 · 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 12 and 42?

    12 · 42 · Lowest common multiple (LCM)

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

    21 · 28 · Lowest common multiple (LCM)

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

    12 · 18 · Lowest common multiple (LCM)

  4. 4. What is the lowest common multiple (LCM) of 33 and 55?

    33 · 55 · Lowest common multiple (LCM)

  5. 5. What is the lowest common multiple (LCM) of 8 and 10?

    8 · 10 · Lowest common multiple (LCM)

  6. 6. What is the lowest common multiple (LCM) of 28 and 35?

    28 · 35 · Lowest common multiple (LCM)

  7. 7. What is the lowest common multiple (LCM) of 55 and 77?

    55 · 77 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 35 and 49?

    35 · 49 · Lowest common multiple (LCM)

  9. 9. What is the lowest common multiple (LCM) of 44 and 77?

    44 · 77 · Lowest common multiple (LCM)

  10. 10. What is the lowest common multiple (LCM) of 36 and 45?

    36 · 45 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 30 and 42?

    30 · 42 · Lowest common multiple (LCM)

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

    6 · 10 · Lowest common multiple (LCM)
12 questions · Seed 61 · 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 12 and 42?

    84

    The highest common factor of 12 and 42 is 6, so LCM = (12 × 42) ÷ 6 = 84.

  2. 2. 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.

  3. 3. 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.

  4. 4. What is the lowest common multiple (LCM) of 33 and 55?

    165

    The highest common factor of 33 and 55 is 11, so LCM = (33 × 55) ÷ 11 = 165.

  5. 5. What is the lowest common multiple (LCM) of 8 and 10?

    40

    The highest common factor of 8 and 10 is 2, so LCM = (8 × 10) ÷ 2 = 40.

  6. 6. What is the lowest common multiple (LCM) of 28 and 35?

    140

    The highest common factor of 28 and 35 is 7, so LCM = (28 × 35) ÷ 7 = 140.

  7. 7. What is the lowest common multiple (LCM) of 55 and 77?

    385

    The highest common factor of 55 and 77 is 11, so LCM = (55 × 77) ÷ 11 = 385.

  8. 8. What is the lowest common multiple (LCM) of 35 and 49?

    245

    The highest common factor of 35 and 49 is 7, so LCM = (35 × 49) ÷ 7 = 245.

  9. 9. What is the lowest common multiple (LCM) of 44 and 77?

    308

    The highest common factor of 44 and 77 is 11, so LCM = (44 × 77) ÷ 11 = 308.

  10. 10. What is the lowest common multiple (LCM) of 36 and 45?

    180

    The highest common factor of 36 and 45 is 9, so LCM = (36 × 45) ÷ 9 = 180.

  11. 11. What is the lowest common multiple (LCM) of 30 and 42?

    210

    The highest common factor of 30 and 42 is 6, so LCM = (30 × 42) ÷ 6 = 210.

  12. 12. 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.

12 questions · Seed 61 · Age guidance, not curriculum certification