SOLUTION: A large pump can filla 77,000 gallon reservoir in 7 hours. Working together, the large pump and a smaller one can fill the reservoir in 6 hours. How long would it take the smaller
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Question 191641: A large pump can filla 77,000 gallon reservoir in 7 hours. Working together, the large pump and a smaller one can fill the reservoir in 6 hours. How long would it take the smaller pump to fill the reservoir by itself? Answer by orca(409) (Show Source):
You can put this solution on YOUR website! Let x represent the amount of water the smaller pump can pump per hour.
The amount of water the larger pump can pump per hour is 77000/7 = 11000 gallons/h.
Working together the number of gallons of water they can pump each hour is
11000 + x.
As they can fill the reservoir in 6 hours, we have
6(11000+x)=77000
Solving for x, we have
11000 + x = 77000/6
x = 77000/6-11000
x = 77000/6-66000/6 = 11000/6
Therefore the amount of water the smaller pump can pump per hour is 11000/6.
So the time it takes for the smaller pump to fill the reservoir is
hours.