Solutions by » LCM of two numbers

What is the LCM of 3 and 7?

The LCM of 3 and 7 is 21.

Steps to find LCM

  1. Find the prime factorization of 3
    3 = 3
  2. Find the prime factorization of 7
    7 = 7
  3. Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the LCM:

    LCM = 3 × 7
  4. LCM = 21

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