What is the LCM of 21 and 56?
The LCM of 21 and 56 is 168.
Steps to find LCM
- Find the prime factorization of 21
21 = 3 × 7 - Find the prime factorization of 56
56 = 2 × 2 × 2 × 7 - Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the LCM:
LCM = 2 × 2 × 2 × 3 × 7 - LCM = 168
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Find least common multiple (LCM) of: 42 & 112 63 & 168 105 & 280 147 & 392 3 & 8 42 & 56 21 & 112 63 & 56 21 & 168 105 & 56 21 & 280 147 & 56 21 & 392
LCM Calculator
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