SOLUTION: Solve the equation m/6 + m/4 = 1 for m In the next step it says 12(m/6=m/4)=(1)(12) I do not know where the 12 came from in order to continue the equation.

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Question 654077: Solve the equation m/6 + m/4 = 1 for m
In the next step it says 12(m/6=m/4)=(1)(12)
I do not know where the 12 came from in order to continue the equation.
Answer by Shana-D77(132) (Show Source):
You can put this solution on YOUR website!
Remember adding fractions like 1/4 + 1/6? You have to find a common denominator and the you can add. So the above would be 3/12 + 2/12 = 5/12. The person who started solving this problem used that 12 because 6 and 4 both go into 12. By multiplying by 12 you get rid of the fractions.

That being said, you can solve this problem by finding common denominator instead:

m/6 + m/4 = 1
12 is the common denominator, so:
2m/12 + 3m/12 = 1
5m/12 = 1
Think of this as:
5m/12 = 1/1
And cross-multiply:
5m = 12
m = 12/5