Solutions by everydaycalculation.com

The LCM of 21 and 1 is 21.

- Find the prime factorization of 21

21 = 3 × 7 - Find the prime factorization of 1

1 = 1 - 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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Find least common multiple (LCM) of: 42 & 2 63 & 3 105 & 5 147 & 7 42 & 1 21 & 2 63 & 1 21 & 3 105 & 1 21 & 5 147 & 1 21 & 7

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