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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 14 and 21?

    14 · 21 · Lowest common multiple (LCM)

  2. 2. What is the lowest common multiple (LCM) of 22 and 77?

    22 · 77 · Lowest common multiple (LCM)

  3. 3. What is the lowest common multiple (LCM) of 18 and 24?

    18 · 24 · Lowest common multiple (LCM)

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

    9 · 21 · Lowest common multiple (LCM)

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

    10 · 25 · 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 48 and 84?

    48 · 84 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 30 and 50?

    30 · 50 · Lowest common multiple (LCM)

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

    6 · 10 · Lowest common multiple (LCM)

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

    45 · 63 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 4 and 14?

    4 · 14 · Lowest common multiple (LCM)

  12. 12. What is the lowest common multiple (LCM) of 15 and 18?

    15 · 18 · Lowest common multiple (LCM)
12 questions · Seed 54 · 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 14 and 21?

    42

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

  2. 2. What is the lowest common multiple (LCM) of 22 and 77?

    154

    The highest common factor of 22 and 77 is 11, so LCM = (22 × 77) ÷ 11 = 154.

  3. 3. What is the lowest common multiple (LCM) of 18 and 24?

    72

    The highest common factor of 18 and 24 is 6, so LCM = (18 × 24) ÷ 6 = 72.

  4. 4. 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.

  5. 5. 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.

  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 48 and 84?

    336

    The highest common factor of 48 and 84 is 12, so LCM = (48 × 84) ÷ 12 = 336.

  8. 8. 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.

  9. 9. 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.

  10. 10. 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.

  11. 11. What is the lowest common multiple (LCM) of 4 and 14?

    28

    The highest common factor of 4 and 14 is 2, so LCM = (4 × 14) ÷ 2 = 28.

  12. 12. What is the lowest common multiple (LCM) of 15 and 18?

    90

    The highest common factor of 15 and 18 is 3, so LCM = (15 × 18) ÷ 3 = 90.

12 questions · Seed 54 · 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 14 and 21?

    14 · 21 · Lowest common multiple (LCM)

  2. 2. What is the lowest common multiple (LCM) of 22 and 77?

    22 · 77 · Lowest common multiple (LCM)

  3. 3. What is the lowest common multiple (LCM) of 18 and 24?

    18 · 24 · Lowest common multiple (LCM)

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

    9 · 21 · Lowest common multiple (LCM)

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

    10 · 25 · 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 48 and 84?

    48 · 84 · Lowest common multiple (LCM)

  8. 8. What is the lowest common multiple (LCM) of 30 and 50?

    30 · 50 · Lowest common multiple (LCM)

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

    6 · 10 · Lowest common multiple (LCM)

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

    45 · 63 · Lowest common multiple (LCM)

  11. 11. What is the lowest common multiple (LCM) of 4 and 14?

    4 · 14 · Lowest common multiple (LCM)

  12. 12. What is the lowest common multiple (LCM) of 15 and 18?

    15 · 18 · Lowest common multiple (LCM)
12 questions · Seed 54 · 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 14 and 21?

    42

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

  2. 2. What is the lowest common multiple (LCM) of 22 and 77?

    154

    The highest common factor of 22 and 77 is 11, so LCM = (22 × 77) ÷ 11 = 154.

  3. 3. What is the lowest common multiple (LCM) of 18 and 24?

    72

    The highest common factor of 18 and 24 is 6, so LCM = (18 × 24) ÷ 6 = 72.

  4. 4. 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.

  5. 5. 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.

  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 48 and 84?

    336

    The highest common factor of 48 and 84 is 12, so LCM = (48 × 84) ÷ 12 = 336.

  8. 8. 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.

  9. 9. 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.

  10. 10. 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.

  11. 11. What is the lowest common multiple (LCM) of 4 and 14?

    28

    The highest common factor of 4 and 14 is 2, so LCM = (4 × 14) ÷ 2 = 28.

  12. 12. What is the lowest common multiple (LCM) of 15 and 18?

    90

    The highest common factor of 15 and 18 is 3, so LCM = (15 × 18) ÷ 3 = 90.

12 questions · Seed 54 · Age guidance, not curriculum certification