SOLUTION: It takes jane 15 hours to paint a house. It takes john 18 hours to paint the same house. How long will it take both of them, working together, to paint the house?

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Question 410057: It takes jane 15 hours to paint a house. It takes john 18 hours to paint the same house. How long will it take both of them, working together, to paint the house?
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
It takes jane 15 hours to paint a house. It takes john 18 hours to paint the same house. How long will it take both of them, working together, to paint the house?
.
Let x = time(hours) it takes for both
then
x(1/15 + 1/18) = 1
multiplying both sides by (15)(18):
x(1/15 + 1/18) = 1
x(18 + 15) = (15)(18)
x(33) = 270
x = 8.182 hours
or
x = 8 hours and 11 minutes