What is the LCM of 20 and 42?
The LCM of 20 and 42 is 420.
Steps to find LCM
- Find the prime factorization of 20
20 = 2 × 2 × 5 - Find the prime factorization of 42
42 = 2 × 3 × 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: 40 & 84 10 & 21 60 & 126 100 & 210 140 & 294 40 & 42 20 & 84 60 & 42 20 & 126 100 & 42 20 & 210 140 & 42 20 & 294
LCM Calculator
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