SOLUTION: The intake pipe can fill a certain tank in 6 h when the outlet pipe is closed, but with the outlet pipe open it takes 9 h. How long would it take to the outlet pipe to empty a ful

Algebra ->  Rate-of-work-word-problems -> SOLUTION: The intake pipe can fill a certain tank in 6 h when the outlet pipe is closed, but with the outlet pipe open it takes 9 h. How long would it take to the outlet pipe to empty a ful      Log On


   

Question 167938This question is from textbook
: The intake pipe can fill a certain tank in 6 h when the outlet pipe is closed, but with the outlet pipe open it takes 9 h. How long would it take to the outlet pipe to empty a full tank? This question is from textbook

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The intake pipe can fill a certain tank in 6 h when the outlet pipe is closed,
but with the outlet pipe open it takes 9 h. How long would it take to the
outlet pipe to empty a full tank?
:
Let t = time for the outlet pipe to empty the tank.
Let the full tank = 1
:
Filling is positive, draining is negative
:
9%2F6 - 9%2Ft = 1
:
Multiply equation by 6t, to get rid of the denominators:
9t - 6(9) = 6t
:
9t - 54 = 6t
:
9t - 6t = 54
:
3t = 54
t = 54%2F3
t = 18 hrs to empty the full tank
;
:
Check solution:
9%2F6 - 9%2F18 = 1
3%2F2 - 1%2F2 = 1