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Least common multiple (LCM) worksheets Grades 4–5

Find the smallest number that both numbers divide into.

The front of the free least common multiple (LCM) worksheet
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Free · Worked example · 38 problems · Answer key · US Letter

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How to do it

The smallest number both divide into. List multiples of the larger number.

LCM of 8 and 15=120\text{LCM of }8\ \text{and }15 = 120
Multiples of 15:15,30,45,60,75,90,105,120\text{Multiples of }15: 15, 30, 45, 60, 75, 90, 105, 120
First one that 8 divides: 120\text{First one that }8\ \text{divides: }120

Example problems

  1. LCM of 5 and 9=\text{LCM of }5\ \text{and }9 =
  2. LCM of 2 and 15=\text{LCM of }2\ \text{and }15 =
  3. LCM of 7 and 13=\text{LCM of }7\ \text{and }13 =
  4. LCM of 5 and 15=\text{LCM of }5\ \text{and }15 =

Factors, multiples and prime numbers

  1. Divisibility rules
  2. Factor pairs
  3. Listing factors
  4. Prime and composite numbers
  5. Prime factorization
  6. Greatest common factor (GCF)
  7. Least common multiple (LCM)
  8. GCF and LCM mixed practice