SOLUTION: A project is assigned to D and F. If F works on the project alone, he will take 15 more days than D works alone.Now F works on the project alone for 8 days, then D joins and they w

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A project is assigned to D and F. If F works on the project alone, he will take 15 more days than D works alone.Now F works on the project alone for 8 days, then D joins and they w      Log On


   



Question 859001: A project is assigned to D and F. If F works on the project alone, he will take 15 more days than D works alone.Now F works on the project alone for 8 days, then D joins and they work together for 10 days. After that F leaves and D needs to work alone for 8 more days to finish the project. Find the number of days for D to finish the project alone.
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
already answered
f=d+15,
8/f+10/f+10/d+8/d=1
18/f+18/d=1,
f=d+15,
d = 30, f = 45
18/45+18/30=1
2/5+3/5=1