document.write( "Question 498679: I have this problem from school and i need to get this done. I have tried toyed around with this problem for 1 hour and don't seem to get anywhere. I have tried to replace variables and tried the quadratic formula but nothing seems to work. If you could help that would be amazing.\r
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\n" ); document.write( "\n" ); document.write( "Pipe A can fill a tank in 6 hours, and pipe B can fill it in 2 hours less time than it take drain pipe C to empty the tank. With all three pipes open it takes 3 hours 20 minutes to fill the tank. How long would it take pipe C to empty it???????
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Algebra.Com's Answer #337137 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!
Pipe A can fill a tank in 6 hours, and pipe B can fill it in 2 hours less time than it take drain pipe C to empty the tank. With all three pipes open it takes 3 hours 20 minutes to fill the tank. How long would it take pipe C to empty it
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document.write( "Make this chart:\r\n" );
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document.write( "               Number of     Time to      Rate in\r\n" );
document.write( "              tanks filled    fill       tanks/hours\r\n" );
document.write( "Pipe A\r\n" );
document.write( "Pipe B\r\n" );
document.write( "Drain C\r\n" );
document.write( "All three\r\n" );
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document.write( "The number of tanks filled is 1 for each of those except Drain C, and\r\n" );
document.write( "we put -1 for the number of tanks it filled. We can fill in the times\r\n" );
document.write( "for C and All three from the problem, and we get this:\r\n" );
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document.write( "               Number of     Time to      Rate in\r\n" );
document.write( "              tanks filled    fill       tanks/hours\r\n" );
document.write( "Pipe A            1            6  \r\n" );
document.write( "Pipe B            1           \r\n" );
document.write( "Drain C          -1            \r\n" );
document.write( "All three         1           3 1/3\r\n" );
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document.write( "Let the time for C to drain be x.  Then B's time to fill is x-2.\r\n" );
document.write( "Fill those in:\r\n" );
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document.write( "               Number of     Time to      Rate in\r\n" );
document.write( "              tanks filled    fill       tanks/hours\r\n" );
document.write( "Pipe A            1            6           \r\n" );
document.write( "Pipe B            1           x-2         \r\n" );
document.write( "Drain C          -1            x           \r\n" );
document.write( "All three         1          3 1/3\r\n" );
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document.write( "Fill in the rates in tanks/hour by dividing the number of\r\n" );
document.write( "tanks filled by the number of hours:\r\n" );
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document.write( "               Number of     Time to      Rate in\r\n" );
document.write( "              tanks filled    fill       tanks/hours\r\n" );
document.write( "Pipe A            1            6            1/6\r\n" );
document.write( "Pipe B            1           x-2          1/(x-2)\r\n" );
document.write( "Drain C          -1            x           -1/x\r\n" );
document.write( "All three         1          3 1/3          \r\n" );
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document.write( "First we simplify the last term: \r\n" );
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document.write( "The LCD is 30x(x-2) so multiply through by that:\r\n" );
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document.write( ",  \r\n" );
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document.write( "Discard the negative time.\r\n" );
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document.write( "It would take drain C 5 hours to empty the tank. \r\n" );
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document.write( "Edwin

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