<PRE><B>Question 864358</B>
filling the pool or emptying the pool is one job

filling 24 hours so it does 1/24 of the job in 1 hour

emptying = 36 hours
so the leak does 1/36 of the job in 1 hour

effective job done in 1 hour
1/24 - 1/36

LCM

(3-2)/72

1/72 of the job is done in 1 hour

It will take 72 hours to fill the pool 

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