Solutions by everydaycalculation.com

The LCM of 21 and 2 is 42.

- Find the prime factorization of 21

21 = 3 × 7 - Find the prime factorization of 2

2 = 2 - Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the LCM:

LCM = 2 × 3 × 7 - LCM =
**42**

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Find least common multiple (LCM) of: 42 & 4 63 & 6 105 & 10 147 & 14 42 & 2 21 & 4 63 & 2 21 & 6 105 & 2 21 & 10 147 & 2 21 & 14

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