What is the LCM of 3 and 21?
The LCM of 3 and 21 is 21.
Steps to find LCM
- Find the prime factorization of 3
3 = 3 - Find the prime factorization of 21
21 = 3 × 7 - Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the LCM:
LCM = 3 × 7 - LCM = 21
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