SOLUTION: A cold water pipe can fill a swimming pool in 10 hours, and a hot water pipe can fill the pool in 15 hours. How long will it take to fill the pool if both pipes are left open?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A cold water pipe can fill a swimming pool in 10 hours, and a hot water pipe can fill the pool in 15 hours. How long will it take to fill the pool if both pipes are left open?      Log On


   



Question 961196: A cold water pipe can fill a swimming pool in 10 hours, and a hot water pipe can fill the pool in 15 hours. How long will it take to fill the pool if both pipes are left open?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A cold water pipe can fill a swimming pool in 10 hours, and a hot water pipe can fill the pool in 15 hours. How long will it take to fill the pool if both pipes are left open?
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cold water rate:: 1/10 job/hr
hot water rate:: 1/15 job/hr
together rate:: 1/x job/hr
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Equation:
rate + rate = together rate
1/10 + 1/15 = 1/x
15x + 10x = 150
25x = 150
x = 6 (# of hours to do the job together)
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Cheers,
Stan H.
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