SOLUTION: Pipe A can fill the swimming pool in 5 hours, and Pipe B can fill the same swimming pool in 7 hours. lf both Pipe A and Pipe B are used to fill the swimming pool at the same ti

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Pipe A can fill the swimming pool in 5 hours, and Pipe B can fill the same swimming pool in 7 hours. lf both Pipe A and Pipe B are used to fill the swimming pool at the same ti      Log On


   

Question 1200178: Pipe A can fill the swimming pool in 5 hours,
and Pipe B can fill the same swimming pool in 7 hours.
lf both Pipe A and Pipe B are used to fill the swimming pool at the same time,
how long does it take to fill the pool?
Answer by ikleyn(52817) About Me  (Show Source):
You can put this solution on YOUR website!
.
Pipe A can fill the swimming pool in 5 hours,
and Pipe B can fill the same swimming pool in 7 hours.
lf both Pipe A and Pipe B are used to fill the swimming pool at the same time,
how long does it take to fill the pool?
~~~~~~~~~~~~~~~ 

Pipe A fills 1/5 of the swimming pool volume each hour.

Pipe B fills 1/7 of the swimming pool volume each hour.


If both pipes are used at the same time, they fill

    1%2F5+%2B+1%2F7 = 7%2F35+%2B+5%2F35 = 12%2F35  

of the pool volume each hour.


It means that the two pipes will fill the swimming pool in 

    35%2F12 = 2 11%2F12 hours = 2 hours and 55 minutes.    ANSWER

Solved.