SOLUTION: One pump can fill a gasoline storage in 8 hours. With a second pump working simultaneously, the tank can be filled in 3 hours. How long would it take the second pump to fill the th

Algebra ->  Rate-of-work-word-problems -> SOLUTION: One pump can fill a gasoline storage in 8 hours. With a second pump working simultaneously, the tank can be filled in 3 hours. How long would it take the second pump to fill the th      Log On


   

Question 1017288: One pump can fill a gasoline storage in 8 hours. With a second pump working simultaneously, the tank can be filled in 3 hours. How long would it take the second pump to fill the the tank alone?
Answer by ikleyn(53937) About Me  (Show Source):
You can put this solution on YOUR website!
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One pump can fill a gasoline storage in 8 hours. With a second pump working simultaneously, the tank can be filled in 3 hours.
How long would it take the second pump to fill the the tank alone?
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The rate of the first pump is 1%2F8 of the tank volume per hour.

The rate of the two pipes, when they work simultaneously, is 1%2F3 of the tank volume per hour.

Hence, the rate of the second pipe, when it works alone, is 

1%2F3 - 1%2F8 = 8%2F24 - 3%2F24 = %288-3%29%2F24 = 5%2F24

of the tank volume per hour.

It means that it takes 24%2F5 of an hour for the second pipe to fill the tank if it works alone.

24%2F5 hours = 4 hours and 48 minutes.