document.write( "Question 318958: A water tank has an inlet pipe and a drain pipe. A full tank can be emptied in 30 minutes if the drain is opened and an empty tank can be filled in 45 minutes with the inlet pipe opened. If both pipes are accidentally opened when the tank is full, then how long will it take to empty the tank? \n" ); document.write( "
Algebra.Com's Answer #228324 by stanbon(75887)\"\" \"About 
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A water tank has an inlet pipe and a drain pipe.
\n" ); document.write( "A full tank can be emptied in 30 minutes if the drain is opened and an empty tank can be filled in 45 minutes with the inlet pipe opened.
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\n" ); document.write( "Drain pipe DATA:
\n" ); document.write( "time = (1/2) hr/job ; rate = 2 job/hr
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\n" ); document.write( "Inlet pipe DATA:
\n" ); document.write( "time = (3/4) hr/job ; rate = (4/3) job/hr
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\n" ); document.write( "If both pipes are accidentally opened when the tank is full, then how long will it take to empty the tank?
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\n" ); document.write( "Together DATA:
\n" ); document.write( "time = x hr/job ; rate = 1/x job/hr
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\n" ); document.write( "Equation:
\n" ); document.write( "drain rate - fill rate = together rate
\n" ); document.write( "2 - (4/3) = 1/x
\n" ); document.write( "2/3 = 1/x
\n" ); document.write( "x = 3/2 hrs to drain the tank
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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