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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 30 and 50?

    30 · 50 · Lowest common multiple (LCM)

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

    12 · 16 · Lowest common multiple (LCM)

  3. 3. What is the lowest common multiple (LCM) of 45 and 63?

    45 · 63 · Lowest common multiple (LCM)

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

    8 · 10 · Lowest common multiple (LCM)

  5. 5. What is the lowest common multiple (LCM) of 9 and 21?

    9 · 21 · Lowest common multiple (LCM)

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

    10 · 12 · Lowest common multiple (LCM)

  7. 7. What is the lowest common multiple (LCM) of 10 and 25?

    10 · 25 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 27 and 36?

    27 · 36 · Lowest common multiple (LCM)

  9. 9. What is the lowest common multiple (LCM) of 20 and 25?

    20 · 25 · Lowest common multiple (LCM)

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

    20 · 70 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 21 and 49?

    21 · 49 · Lowest common multiple (LCM)

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

    55 · 77 · Lowest common multiple (LCM)
12 questions · Seed 68 · 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 30 and 50?

    150

    The highest common factor of 30 and 50 is 10, so LCM = (30 × 50) ÷ 10 = 150.

  2. 2. 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.

  3. 3. What is the lowest common multiple (LCM) of 45 and 63?

    315

    The highest common factor of 45 and 63 is 9, so LCM = (45 × 63) ÷ 9 = 315.

  4. 4. 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.

  5. 5. What is the lowest common multiple (LCM) of 9 and 21?

    63

    The highest common factor of 9 and 21 is 3, so LCM = (9 × 21) ÷ 3 = 63.

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

    60

    The highest common factor of 10 and 12 is 2, so LCM = (10 × 12) ÷ 2 = 60.

  7. 7. What is the lowest common multiple (LCM) of 10 and 25?

    50

    The highest common factor of 10 and 25 is 5, so LCM = (10 × 25) ÷ 5 = 50.

  8. 8. What is the lowest common multiple (LCM) of 27 and 36?

    108

    The highest common factor of 27 and 36 is 9, so LCM = (27 × 36) ÷ 9 = 108.

  9. 9. What is the lowest common multiple (LCM) of 20 and 25?

    100

    The highest common factor of 20 and 25 is 5, so LCM = (20 × 25) ÷ 5 = 100.

  10. 10. 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.

  11. 11. What is the lowest common multiple (LCM) of 21 and 49?

    147

    The highest common factor of 21 and 49 is 7, so LCM = (21 × 49) ÷ 7 = 147.

  12. 12. 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.

12 questions · Seed 68 · 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 30 and 50?

    30 · 50 · Lowest common multiple (LCM)

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

    12 · 16 · Lowest common multiple (LCM)

  3. 3. What is the lowest common multiple (LCM) of 45 and 63?

    45 · 63 · Lowest common multiple (LCM)

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

    8 · 10 · Lowest common multiple (LCM)

  5. 5. What is the lowest common multiple (LCM) of 9 and 21?

    9 · 21 · Lowest common multiple (LCM)

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

    10 · 12 · Lowest common multiple (LCM)

  7. 7. What is the lowest common multiple (LCM) of 10 and 25?

    10 · 25 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 27 and 36?

    27 · 36 · Lowest common multiple (LCM)

  9. 9. What is the lowest common multiple (LCM) of 20 and 25?

    20 · 25 · Lowest common multiple (LCM)

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

    20 · 70 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 21 and 49?

    21 · 49 · Lowest common multiple (LCM)

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

    55 · 77 · Lowest common multiple (LCM)
12 questions · Seed 68 · 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 30 and 50?

    150

    The highest common factor of 30 and 50 is 10, so LCM = (30 × 50) ÷ 10 = 150.

  2. 2. 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.

  3. 3. What is the lowest common multiple (LCM) of 45 and 63?

    315

    The highest common factor of 45 and 63 is 9, so LCM = (45 × 63) ÷ 9 = 315.

  4. 4. 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.

  5. 5. What is the lowest common multiple (LCM) of 9 and 21?

    63

    The highest common factor of 9 and 21 is 3, so LCM = (9 × 21) ÷ 3 = 63.

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

    60

    The highest common factor of 10 and 12 is 2, so LCM = (10 × 12) ÷ 2 = 60.

  7. 7. What is the lowest common multiple (LCM) of 10 and 25?

    50

    The highest common factor of 10 and 25 is 5, so LCM = (10 × 25) ÷ 5 = 50.

  8. 8. What is the lowest common multiple (LCM) of 27 and 36?

    108

    The highest common factor of 27 and 36 is 9, so LCM = (27 × 36) ÷ 9 = 108.

  9. 9. What is the lowest common multiple (LCM) of 20 and 25?

    100

    The highest common factor of 20 and 25 is 5, so LCM = (20 × 25) ÷ 5 = 100.

  10. 10. 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.

  11. 11. What is the lowest common multiple (LCM) of 21 and 49?

    147

    The highest common factor of 21 and 49 is 7, so LCM = (21 × 49) ÷ 7 = 147.

  12. 12. 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.

12 questions · Seed 68 · Age guidance, not curriculum certification