document.write( "Question 811549: if 3 water pumps can empty a water tank in 80 minutes, it will take 4 pumps ? minutes to empty the same tank. \n" ); document.write( "
Algebra.Com's Answer #488785 by josgarithmetic(39630)\"\" \"About 
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If 80 minutes for 3 pumps, then 3 times longer for just 1 pump.
\n" ); document.write( "One pump empties the water tank in \"3%2A80=240\" minutes.\r
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\n" ); document.write( "\n" ); document.write( "FOUR pumps go at the rate of \"1%2F240%2B1%2F240%2B1%2F240%2B1%2F240=4%281%2F240%29\" tanks per minute. This is 60 minutes for four pumps.
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