SOLUTION: It takes pipe A 2 hours longer than pipe B to fill up an empty pool. Using both pipes, it takes 2.4 hours to fill up the same pool. How long does it take each pipe, working alone

Algebra ->  Rate-of-work-word-problems -> SOLUTION: It takes pipe A 2 hours longer than pipe B to fill up an empty pool. Using both pipes, it takes 2.4 hours to fill up the same pool. How long does it take each pipe, working alone      Log On


   

Question 973120: It takes pipe A 2 hours longer than pipe B to fill up an empty pool. Using
both pipes, it takes 2.4 hours to fill up the same pool. How long does it take
each pipe, working alone to fill up the pool?
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
It takes pipe A 2 hours longer than pipe B to fill up an empty pool. Using
both pipes, it takes 2.4 hours to fill up the same pool. How long does it take
each pipe, working alone to fill up the pool?
***
let x=amt of time it takes pipe B to fill up the pool working alone
Its work rate=1/x
x+2=amt of time it takes pipe A to fill up the pool working alone
Its work rate=1/(x+2)
2.4=amt of time it takes pipe to fill up the pool using both pipes
Their work rate=1/2.4
1%2Fx%2B1%2F%28x%2B2%29=1%2F2.4
lcd: 2.4x(x+2)
2.4(x+2)+2.4x=x(x+2)
2.4x+4.8+2.4x=x^2+2x
x^2-2.8x-4.8=0
(x-4)(x+1.2)=0
x=4
x+2=6
x=4
amt of time it takes pipe B to fill up the pool working alone=4 hrs
amt of time it takes pipe A to fill up the pool working alone=6 hrs