SOLUTION: John is trying to drain a swimming pool. He has two pumps, but he can only use one at a time. He knows that the time a pump takes to drain the pool varies inversely with the power

Question 751593: John is trying to drain a swimming pool. He has two pumps, but he can only use one at a time. He knows that the time a pump takes to drain the pool varies inversely with the power in watts of the pump. His old pump is a 40 watt pump, and it can drain the pool in 5 hours. How long would the job take if he uses his new 100 watt pump?
Answer by Cromlix(4381) (Show Source): You can put this solution on YOUR website!
Formula would be: Time = k/Watts (k = constant
of variation)
Using old pump 5 hrs = k/40 watts
Therefore k = 200
Formula - Time = 200/ Watts
Using the new pump => Time = 200/ 100 Watts
Time = 2 hours.
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