document.write( "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?
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Algebra.Com's Answer #586062 by josgarithmetic(39617)\"\" \"About 
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The job is to fill \"3%2F4\" of the pool. Uniform rates, flow for filling a vessel.\r
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