document.write( "Question 441173: a water pump fills a reservoir in 4 hours. Another pump empties the same reservoir in 8 hours. If both pumps are turned on accidentally, how long will it take to fill the empty reservoir? \n" ); document.write( "
Algebra.Com's Answer #312293 by jorel1380(3719)\"\" \"About 
You can put this solution on YOUR website!
t/4-t/8=1
\n" ); document.write( "2t-t=8
\n" ); document.write( "t=8
\n" ); document.write( "It will take 8 hours to fill the reservoir.
\n" ); document.write( "1/4-1/8=1/t
\n" ); document.write( "2/8-1/8=1/t
\n" ); document.write( "1/8=1/t
\n" ); document.write( "t=8..
\n" ); document.write( "
\n" );