SOLUTION: Tom can paint a room in 5 hours; if he works with Tim, they can paint together the same room in 2 hours. How long does it take for Tim to paint the room by himself? I came up wi

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Tom can paint a room in 5 hours; if he works with Tim, they can paint together the same room in 2 hours. How long does it take for Tim to paint the room by himself? I came up wi      Log On


   

Question 465706: Tom can paint a room in 5 hours; if he works with Tim, they can paint together the same room in 2 hours. How long does it take for Tim to paint the room by himself?
I came up with 1/5 – 1/2 = x
I think X would be 3, that Tim could paint the room in 3 hours. But I am not sure. Please help any advice would be great, tahnk you!
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Tom can paint a room in 5 hours; if he works with Tim, they can paint together the same room in 2 hours.
How long does it take for Tim to paint the room by himself?
:
Here is a simple and understandable method of doing these shared work problems
:
Let t = Tim's time working alone
Let the completed job = 1
:
Each man will do a fraction of the job; the two fractions must add up to 1 (a complete job)
:
2%2F5 + 2%2Ft = 1
Multiply by 5t to clear the denominators, results
2t + 5(2) = 5t
2t + 10 = 5t
10 = 5t - 2t
10 = 3t
t = 10%2F3
t = 31%2F3 hrs Tim working alone
:
:
See if these two fractions add up to 1
2/5 + 2/3.33
.4 + .6 = 1