SOLUTION: A clerk is assigned a job that she can complete in 8 hours. After she has been working 2 hours, another clerk, who is able to do the job in 10 hours, is assigned to help her. In ho

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A clerk is assigned a job that she can complete in 8 hours. After she has been working 2 hours, another clerk, who is able to do the job in 10 hours, is assigned to help her. In ho      Log On


   

Question 211471: A clerk is assigned a job that she can complete in 8 hours. After she has been working 2 hours, another clerk, who is able to do the job in 10 hours, is assigned to help her. In how many hours will the clerks, working together, finish the job?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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A clerk is assigned a job that she can complete in 8 hours.
After she has been working 2 hours, another clerk, who is able to do the job in 10 hours, is assigned to help her.
In how many hours will the clerks, working together, finish the job?
:
Let x = time working together
then
(x+2) = total time working by the 1st clerk
:
Let the completed job = 1
;
A typical shared work equation:
%28%28x%2B2%29%29%2F8 + x%2F10 = 1
Multiply equation by 40 to get rid of the denominators, results:
5(x+2) + 4x = 40
5x + 10 + 4x = 40
5x + 4x = 40 - 10
9x = 30
x = 30%2F9
x = 31%2F3 hrs working together
:
;
Check solution; (1st clerk worked 5.33 hrs)
5.33/8 + 3.33/10 =
.67 + .33 = 1