SOLUTION: Harry can paint a room in 3 hours, and kerry can paint it in 4 hours. how long will it take if they work together?

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Question 269212: Harry can paint a room in 3 hours, and kerry can paint it in 4 hours. how long will it take if they work together?
Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
Let x be the number of hours they can both do the work. The equation weill be set up as follows:
1/3 + 1/4 = 1/x Multiply by 12x to give us:
4x+3x=12 Combine and divide each side by 7 to get:
x=12/7 hours or rewritten as 1 5/7 hours
RJ
There is a book that might help:
www.math-unlock.com