SOLUTION: A large pipe can be filled by one pipe in 20 hours. A second pipe can be fill the tanks in 15 hours. if the first pipe was open for 16 hours and then closed, how long would it take

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A large pipe can be filled by one pipe in 20 hours. A second pipe can be fill the tanks in 15 hours. if the first pipe was open for 16 hours and then closed, how long would it take      Log On


   

Question 933465: A large pipe can be filled by one pipe in 20 hours. A second pipe can be fill the tanks in 15 hours. if the first pipe was open for 16 hours and then closed, how long would it take to fill tank of the inlet pipe was opened after the first was closed?
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Large Pipe, rate of fill is 1/20 tank per hours.
Second Pipe, rate of fill is 1/15 tank per hours.

Time for each pipe used separately, 16 and unknown t. ONE tanks-worth.

highlight%28%281%2F20%29%2A16%2B%281%2F15%29t=1%29.
Solve for t, in hours.