document.write( "Question 258175: A water tank has an inlet pipe and a drain
\n" ); document.write( "pipe. A full tank can be emptied in 30 minutes if the drain
\n" ); document.write( "is opened and an empty tank can be filled in 45 minutes
\n" ); document.write( "with the inlet pipe opened. If both pipes are accidentally
\n" ); document.write( "opened when the tank is full, then how long will it take to
\n" ); document.write( "empty the tank? \n" ); document.write( "

Algebra.Com's Answer #190046 by palanisamy(496) $\"\"$ $\"About$

You can put this solution on YOUR website!
Given, a full tank can be emptied in 30 minutes if the drain is opened.
\n" ); document.write( "So in 1 minute 1/30 of the tank can be emptied.
\n" ); document.write( "And an empty tank can be filled in 45 minutes with the inlet pipe opened.
\n" ); document.write( "So in 1 minute 1/45 of the tank can be filled.
\n" ); document.write( "If both are opened, in one minute, [(1/30)-(1/45)]of the tank can be emptied.
\n" ); document.write( "Time taken to empty the full tank = 1/[(1/30)-(1/45)]
\n" ); document.write( " = 1/[(45-30)/45*30]
\n" ); document.write( " = 45*30/15
\n" ); document.write( " = 3*30
\n" ); document.write( " = 90 minutes \n" ); document.write( "

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