Answers

The LCM of 21 and 6 is 42.

Steps to find LCM

1. Find the prime factorization of 21
   21 = 3 × 7
2. Find the prime factorization of 6
   6 = 2 × 3
3. Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the LCM:
   
   LCM = 2 × 3 × 7
4. LCM = 42

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Find least common multiple (LCM) of: 42 & 12 63 & 18 7 & 2 105 & 30 147 & 42 42 & 6 21 & 12 63 & 6 21 & 18 105 & 6 21 & 30 147 & 6 21 & 42

LCM Calculator

Enter two numbers separate by comma. To find least common multiple (LCM) of more than two numbers, click here.