SOLUTION: If A can finish a job 50% faster than B and 20% faster than C, and together they can finish the job in 4 hours, how long would it take A to finish the job alone?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: If A can finish a job 50% faster than B and 20% faster than C, and together they can finish the job in 4 hours, how long would it take A to finish the job alone?      Log On


   



Question 254957: If A can finish a job 50% faster than B and 20% faster than C, and together they can finish the job in 4 hours, how long would it take A to finish the job alone?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If A can finish a job 50% faster than B and 20% faster than C, and together they can finish the job in 4 hours, how long would it take A to finish the job alone?
:
If A can finish a job 50% faster than B and 20% faster than C, and together they can finish the job in 4 hours, how long would it take A to finish the job alone?
:
let t = time required by A alone
then
1.5t = time required by B
and
1.2 = time required by C
:
Let the completed job = 1
:
4%2Ft + 4%2F%281.5t%29 + 4%2F%281.2t%29 = 1
Multiply equation by 6t, results
6(4) + 4(4) + 5(4) = 6t
24 + 16 + 20 = 6t
60 = 6t
t = 60%2F6
t = 10 hrs for A
1.5(10) = 15 hrs for B
1.2(10) = 12 hrs for C
;
:
Check solution on a calc:
4%2F10 + 4%2F15 + 4%2F12 = 1