SOLUTION: If it takes a small inlet pipe 5 hours to fill a pool, a large pipe 2 hours to fill a pool, and a standard oulet pipe 6 hours to empty a pool how long will it take to fill an empty

Algebra ->  Rate-of-work-word-problems -> SOLUTION: If it takes a small inlet pipe 5 hours to fill a pool, a large pipe 2 hours to fill a pool, and a standard oulet pipe 6 hours to empty a pool how long will it take to fill an empty      Log On


   



Question 139247: If it takes a small inlet pipe 5 hours to fill a pool, a large pipe 2 hours to fill a pool, and a standard oulet pipe 6 hours to empty a pool how long will it take to fill an empty pool if all three pipes are in operation?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If it takes a small inlet pipe 5 hours to fill a pool, a large pipe 2 hours to fill a pool, and a standard outlet pipe 6 hours to empty a pool how long will it take to fill an empty pool if all three pipes are in operation?
:
Let t = time (in hrs) required to empty the pool
:
Let the full pool = 1
:
Filling (+) and emptying (-)
:
t%2F5 + t%2F2 - t%2F6 = 1
:
Get rid of the denominators, multiply by 30:
6t + 15t - 5t = 30
:
16t = 30
t = 30%2F16
t = 1.875 hrs
:
:
Confirm solution:
1.875%2F5 + 1.875%2F2 - 1.875%2F6 =
.375 + .9375 - .3125 = 1