document.write( "Question 713986: A tank can be filled in 2 hours. The same tank can be emptied in 6 hours. If the faucet is turned on and the drain is left open, when will the tank overflow? \n" ); document.write( "

Algebra.Com's Answer #438628 by josmiceli(19441) $\"\"$ $\"About$

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The rate of filling is ( 1 tank ) / ( 2 hrs )
\n" ); document.write( "The rate of draining is ( -1 tank ) / ( 6 hrs )
\n" ); document.write( "Let $\"+t+\"$ = time in hrs when tank starts to overflow
\n" ); document.write( "-------------
\n" ); document.write( "I'm assuming that the tank starts out empty
\n" ); document.write( "Add the rates to get the total rate
\n" ); document.write( "Draining is a negative rate
\n" ); document.write( " $\"+1%2F2+-+1%2F6+=+1%2Ft+\"$
\n" ); document.write( "Multiply both sides by $\"+6t+\"$
\n" ); document.write( " $\"+3t+-+t+=+6+\"$
\n" ); document.write( " $\"+2t+=+6+\"$
\n" ); document.write( " $\"+t+=+3+\"$
\n" ); document.write( "The tank starts to overflow in 3 hrs
\n" ); document.write( " \n" ); document.write( "

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