What is the LCM of 12 15 and 36?

Answer 1

36 is a multiple of 12, so any multiple of 36 is also a multiple of 12.

36 = 3*12
15 = 3*5

LCM[12, 15, 36] = 3*5*12 = 180
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The LCM of a pair of numbers is the product of their unique factors and their common factor.

When you know the prime factorization, you can take each factor to the highest power it appears.
12 = 22*3
15 = 3*5
36 = 22*32

LCM = 22*32*5 = 180

Answer 2

LCM(12, 15, 36) = 180