document.write( "Question 270702: An inlet pipe can fill a tank in 10 minutes.. A drain can empty the tank in 12 minutes. If the tank is empty and both the pipe and the drain are open, how long will it take before the tank overflows?
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Algebra.Com's Answer #198244 by ptaylor(2198)\"\" \"About 
You can put this solution on YOUR website!
Let x=time it takes for tank to overflow when both pipes are open and the tank is empty
\n" ); document.write( "When both pipes are open the tank fills at the rate of 1/x tank per min\r
\n" ); document.write( "\n" ); document.write( "Inlet pipe fills at the rate of 1/10 tank per min
\n" ); document.write( "drain empties at the rate of 1/12 tank per min\r
\n" ); document.write( "\n" ); document.write( "So, our equation to solve is:
\n" ); document.write( "1/10 - 1/12=1/x multiply each term by 60x
\n" ); document.write( "6x-5x=60
\n" ); document.write( "x=60 min--------------time it takes for tank to overflow when both pipes are open and the tank is empty\r
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\n" ); document.write( "\n" ); document.write( "CK
\n" ); document.write( "in 60 min inlet pipe fills (1/10)*60 or 6 tanks
\n" ); document.write( "in 60 min drain lets out (1/12)*60 or 5 tanks
\n" ); document.write( "So in 60 min we have a net gain of 1 tank---any more water and it overflows\r
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\n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor \n" ); document.write( "
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