SOLUTION: An inlet pipe on a swimming pool can be used to fill the pool in 21 hours. The drain pipe can be used to empty the pool in 28 hours. If the pool is 1/4 filled and then the inlet pi

Algebra ->  Rate-of-work-word-problems -> SOLUTION: An inlet pipe on a swimming pool can be used to fill the pool in 21 hours. The drain pipe can be used to empty the pool in 28 hours. If the pool is 1/4 filled and then the inlet pi      Log On


   

Question 958957: An inlet pipe on a swimming pool can be used to fill the pool in 21 hours. The drain pipe can be used to empty the pool in 28 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 by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The job is to fill 3%2F4 of the pool. Uniform rates, flow for filling a vessel.

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