SOLUTION: A hot water tap can fill a bath in 7 minutes while a cold water tap can fill the same bath in five minitues.The drain pipe can empty the full bath in 13/3 minutes. The two taps and

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A hot water tap can fill a bath in 7 minutes while a cold water tap can fill the same bath in five minitues.The drain pipe can empty the full bath in 13/3 minutes. The two taps and      Log On


   

Question 1105065: A hot water tap can fill a bath in 7 minutes while a cold water tap can fill the same bath in five minitues.The drain pipe can empty the full bath in 13/3 minutes. The two taps and the drain tap are left open for 5/2 minutes after which the drain pipe is closed. How much longer will it take to fill the bath
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
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hot water tap can fill a bath in 7 minutes while a cold water tap can fill the same bath in five minitues.The drain pipe can empty the full bath in 13/3 minutes.
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Pipe      RATE
HOT       1%2F7
COLD      1%2F5
DRAIN     -3%2F13



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The two taps and the drain tap are left open for 5/2 minutes after which the drain pipe is closed. How much longer will it take to fill the bath?
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x, how much time
%281%2F7%2B1%2F5-3%2F13%29%285%2F2%29%2B%281%2F7%2B1%2F5%29x=1

Multiply left and right by 2*5*7*13, and simplify.

x=2.0994

x is 2 minutes 6 seconds
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