SOLUTION: How do I add fractions? How do I multiply fractions?

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Question 1161457: How do I add fractions?
How do I multiply fractions?

Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!

Multiply fractions by multiplying the numerators and denominators:
Example: (6/100)*(5/9) = 30/900 (= 1/30 in lowest terms)
Example: (1/2)*(1/7) = 1/14
Example: (2/3)*(33) = (2/3)*(33/1) = 66/3 ( = 22 in lowest terms)

Add fractions by finding a common denominator, then add the numerators while leaving the denominator at the common denominator (usually you want to find the least common denominstor):
Example: (1/3) + (4/7) = (7/21) + (12/21) = 19/21
1/3 becomes 7/21 because I need to multiply (1/3) by (7/7) to get the denominstor to be 21. 4/7 becomes 12/21 because (4/7)*(3/3) gets the denominstor to 21.