SOLUTION: One pump can fill a swimming pool in 8 hours and another pump can fill it in 10 hours. If both pumps are opened at the same time, how many hours will it take to fill the pool?

Question 1042459: One pump can fill a swimming pool in 8 hours and another pump can fill it in 10 hours. If both pumps are opened at the same time, how many hours will it take to fill the pool?

Found 2 solutions by rothauserc, ikleyn:
Answer by rothauserc(4718)   (Show Source): You can put this solution on YOUR website!
Let x be the amount of time it takes to fill the pool with both pumps working together, then
:
(1/8) + (1/10) = (1/x)
:
represents amount of pool filled in an hour working together
:
(5/40) + (4/40) = (1/x)
:
9/40 = 1/x
:
9x = 40
:
x = 4.44444 approx 4.4 hours
:
******************************************
it will take 4.4 hours to fill the pool
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:

Answer by ikleyn(52781)   (Show Source): You can put this solution on YOUR website!
For a bunch of similar solved joint work problems see the lessons
    - Using Fractions to solve word problems on joint work,
    - Solving more complicated word problems on joint work,
    - Selected joint-work word problems from the archive
in this site.

Read them and become an expert in solving these problems.

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