Solutions by everydaycalculation.com

The LCM of 21 and 140 is 420.

- Find the prime factorization of 21

21 = 3 × 7 - Find the prime factorization of 140

140 = 2 × 2 × 5 × 7 - Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the LCM:

LCM = 2 × 2 × 3 × 5 × 7 - LCM =
**420**

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Find least common multiple (LCM) of: 42 & 280 63 & 420 105 & 700 147 & 980 3 & 20 42 & 140 21 & 280 63 & 140 21 & 420 105 & 140 21 & 700 147 & 140 21 & 980

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