SOLUTION: A hose takes 15 minutes to fill a swimming pool and the drain empties the pool in twenty minutes. How long will it take to fill the pool if the drain is accidentally left open?

Question 621720: A hose takes 15 minutes to fill a swimming pool and the drain empties the pool in twenty minutes. How long will it take to fill the pool if the drain is accidentally left open?
I need to know how you got the answer also! Please help!!
Found 2 solutions by lynnlo, Alan3354:
Answer by lynnlo(4176) (Show Source): You can put this solution on YOUR website!
it can not be filled
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
A hose takes 15 minutes to fill a swimming pool and the drain empties the pool in twenty minutes. How long will it take to fill the pool if the drain is accidentally left open?
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Each minute, the hose adds 1/15 of the pool, and 1/20 is lost out the drain.
--> (1/15 - 1/20) per minute net gain
= 1/60 of the pool per minute
--> 60 min/pool
60 minutes to fill

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