SOLUTION: Find the least common denominator for fractions with denominators 9 , 12 , and 16

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Question 110642: Find the least common denominator for fractions with denominators 9 , 12 , and 16
Found 2 solutions by MathLover1, scott8148:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

Find the least common denominator for fractions with denominators 9 , 12 , and 16
Method to find LCM:
Factor the numbers into products of powers of prime numbers.
Create a new number multiplying together all the primes occurring in
either number, raised to the higher of the two exponents. That is the
LCM.


factor number+9:
9+=+3+%2A+3
factor number 12:
12+=+2+%2A+2+%2A+3
factor number 16:

16=+2+%2A+2%2A2+%2A+2
LCM+=+2+%2A+2+%2A+2+%2A+2+%2A+3+%2A+3+=144



Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
find the prime factors for each number, and multiply the factors as many times as they most frequently occur
(the example is easier to see)

factors of 9 ... 3,3
factors of 12 ... 2,2,3
factors of 16 ... 2,2,2,2

so the factors of the denominator will be 3,3 (from the 9) and 2,2,2,2 (from the 16) ... 9*16=144

the factors from the 12 (two 2's and one 3) are included in the factors of the 9 (two 3's) and the 16 (four 2's)