SOLUTION: Bob can build a fence in 10 hours, if Frank helps him they can build it in 6 hours. How long would it take Frank to build the fence by himself?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Bob can build a fence in 10 hours, if Frank helps him they can build it in 6 hours. How long would it take Frank to build the fence by himself?      Log On


   



Question 897819: Bob can build a fence in 10 hours, if Frank helps him they can build it in 6 hours. How long would it take Frank to build the fence by himself?
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
rate for Bob (A) alone 10
rate for A & B together 6
1/a+1/b=1/x
1/10+1/b=1/6
1/b=1/6-1/10
1/b=10/60-6/60
1/b=4/60
1/b=1/15
b=15
rate for Frank (B) alone 15