document.write( "Question 631672: one pipe can empty the tank in 4 hours. a second pipe takes 2 hours to do the same job. how long will it take to empty the tank if both pipes are open?
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Algebra.Com's Answer #397742 by nerdybill(7384) $\"\"$ $\"About$

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one pipe can empty the tank in 4 hours. a second pipe takes 2 hours to do the same job. how long will it take to empty the tank if both pipes are open?
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\n" ); document.write( "Let x = time (hours) it takes for both
\n" ); document.write( "then
\n" ); document.write( "x(1/4 + 1/2) = 1
\n" ); document.write( "x(1/4 + 2/4) = 1
\n" ); document.write( "x(3/4) = 1
\n" ); document.write( "x(3) = 4
\n" ); document.write( "x = 4/3 hours
\n" ); document.write( "or
\n" ); document.write( "x = 1 and 1/3 hours
\n" ); document.write( "or
\n" ); document.write( "x = 1 hour and 20 minutes \n" ); document.write( "

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