Problema Solution
An inlet pipe in a swimming pool can be used to fill the pool in 12 hours. The drain pipe can be used to empty the pool in 14 hours. If the pool is 1/4 filled and then the inlet pipe and drain pipe are opened, how long from that time will it take to fill the pool?
Answer provided by our tutors
the amount of hours it would drain without anything into the inlet: 14*(3/4) = 10.5 hours, leaving 3.5 hours to drain the same rate
if 12 hours of inlet is turned on, the rate changes from 14 to (14-12), so let 'x' represent the ratio for the final hours taken:
14*3.5 = (14-12)*(x)
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solve for the remaining hours to drain
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x=24.5
so it will now take 24 1/2 hours to drain