SOLUTION: Working together to pumps can train a certain pool in four hours. If it takes the older pump nine hours to drain the pool by itself how long will it take the newer pump to drain t

Algebra ->  Human-and-algebraic-language -> SOLUTION: Working together to pumps can train a certain pool in four hours. If it takes the older pump nine hours to drain the pool by itself how long will it take the newer pump to drain t      Log On


   

Question 1140982: Working together to pumps can train a certain pool in four hours. If it takes the older pump nine hours to drain the pool by itself how long will it take the newer pump to drain the pool on its own?
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Together, rate is 1%2F4.
Old pump, rate is 1%2F9.
Newer pump, rate is unknown, 1%2Fx.

1%2F9%2B1%2Fx=1%2F4---------solve this for x.

--

x IS THE TIME FOR THE NEWER PUMP TO DO THE JOB BY ITSELF.
COMBINED RATE IS SUM OF THE INDIVIDUAL RATES.
SOLVE THE EQUATION FOR x.