Answer: 30
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Step-by-step explanation
When dealing with two numbers, the LCM formula is
LCM = (x*y)/GCF
The GCF of 10 and 15 is 5, so,
LCM = (10*15)/5 = 30
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Another approach
We can list out the multiples of each value.
10, 20, 30, 40, 50, ...
15, 30, 45, 60, 75, ...
We see the LCM is 30
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A third approach
Find the prime factorization of each given value.
10 = 2*5
15 = 3*5
The unique primes are 2, 3, 5. Each shows up at most once. Multiply out the primes to get 2*3*5 = 30 as the LCM