SOLUTION: An electric pump can fill a tank in 3 hours. Because of a leak in the tank, it took 3 hours 30 min to fill the tank. The leak can drain out all the water of the tank in

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Question 862928: An electric pump can fill a tank in 3 hours. Because of a leak in the tank, it took 3 hours 30 min to fill the tank. The leak can drain out all the water of the tank in
Found 2 solutions by josgarithmetic, lwsshak3:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The filling is an opposite task than the emptying. Work with the rates as TANK per HOUR.

Pump A without leak, 1%2F3 tank per hour
Leak, -1%2Fx tank per hour
Combined A and leakage, 1%2F3.5 tank per hour

Notice very carefully:
Filling the tank is positive, and emptying the tank is negative.
x is the time for the leak alone to empty the tank if started from full.
3.5 hours is the same as 3 hours 30 minutes.

The combined rate of pump A and the leak working at the same time is the sum of their individual rates:
%281%2F3%29%2B%28-1%2Fx%29=1%2F3.5
1%2F3-1%2Fx=1%2F3.5
and you could prefer
highlight%281%2F3%2B1%2Fx=5%2F13%29-----SOLVE FOR x.

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
An electric pump can fill a tank in 3 hours. Because of a leak in the tank, it took 3 hours 30 min to fill the tank. The leak can drain out all the water of the tank in
***
1/3=rate of pump to fill tank by itself with no leak
1/x=rate of leak which empties the full tank by itself
1/3.5=rate at which tank is filled with pump and leak working.
1%2F3-1%2Fx=1%2F3.5
LCD:3x
x-3=3x/3.5
3.5x-10.5=3x
0.5x=10.5
x=21
The leak can drain out all the water of the tank in 21 hrs