Question 232546
Pipe A can fill a tank in 5 hours. Pipe B can fill the tank in 2 hours less time than it takes pipe C to empty it. With all pipes open it takes 3 hours to fill the tank. How long will it take pipe C to empty the tank?
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Pipe A DATA:
filling rate = 1/5 tank/hr
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Pipe C DATA:
filling rate = 1/x tank/hr
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Pipe B DATA:
filling rate = 1/(x-2) tank/hr
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Together DATA:
filling rate = 1/3 tank/hr
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Equation:
rate + rate + rate = together rate
1/5 + 1/x + 1/(x-2) = 1/3
Multiply thru by 15x(x-2):
3x(x-2) + 15(x-2) + 15x = 5x(x-2)
etc.
I'll let you finish this.
Cheers,
Stan H.