SOLUTION: One inlet pipe can fill an empty pool in 8 hours, and a drain can empty the pool in 16 hours. How long will it take the pipe to fill the pool if the drain is left open?

Algebra ->  Probability-and-statistics -> SOLUTION: One inlet pipe can fill an empty pool in 8 hours, and a drain can empty the pool in 16 hours. How long will it take the pipe to fill the pool if the drain is left open?      Log On


   

Question 885097: One inlet pipe can fill an empty pool in 8 hours, and a drain can empty the pool in 16 hours. How long will it take the pipe to fill the pool if the drain is left open?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Sum of the FILL rates. One pipe fills and the other pipe fills LESS THAN ZERO rate.

x = how long to fill if both pipes are open at the same time

1%2F8%2B%28-1%2F16%29=1%2Fx
1%2F8-1%2F16=1%2Fx
2-1=16%2Fx
1%2Ax=16
highlight%28x=16%29 hours