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Method #1
Multiply the two values to get 12*16 = 192
Then divide over the GCF 4 getting 192/4 = 48
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Method #2
List out the multiples of each and see what they have in common
Multiples of 12 = {12, 24, 36, 48, 60, 72, 84, 96, ...}
Multiples of 16 = {16, 32, 48, 64, 80, 96, ...}
We see that 48 is the smallest common multiple.
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Method #3
Find the prime factorization for each
12 = 2*2*3
16 = 2*2*2*2
The unique prime factors are 2 and 3
The prime 2 shows up at most 4 times, so 2^4 = 16 is one factor of the LCM
The prime 3 shows up at most 1 time, so 3^1 = 3 is the other factor of the LCM
The LCM is 3*16 = 48.
