SOLUTION: If Jim and Tom can do a job together in 3.5 hours, and Jim can do the job alone in 4 hours. How long toes it take Tom to do the job alone?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: If Jim and Tom can do a job together in 3.5 hours, and Jim can do the job alone in 4 hours. How long toes it take Tom to do the job alone?      Log On


   



Question 228190: If Jim and Tom can do a job together in 3.5 hours, and Jim can do the job alone in 4 hours. How long toes it take Tom to do the job alone?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If Jim and Tom can do a job together in 3.5 hours, and Jim can do the job alone in 4 hours.
How long toes it take Tom to do the job alone?
:
Let = time required by Tom alone
:
Typical shared work equation
:
let the completed job = 1
:
3.5%2F4 + 3.5%2Ft = 1
multiply equation by 4t, results:
3.5t + 4(3.5) = 4t
:
3.5t + 14 = 4t
:
14 = 4t - 3.5t
:
14 = .5t
:
t = 28 hrs, Tom alone
;
;
Check on a calc: enter: (3.5/4) + (3.5/28) = 1