Solutions by everydaycalculation.com

The LCM of 21 and 56 is 168.

- 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

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