SOLUTION: Workman A's rate of doing work is twice that of Workman B's. One day, A & B work together for 8 hrs, then B due to injury stops and A finishes the rest of the job in 2 hrs. How lon
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Question 984471: Workman A's rate of doing work is twice that of Workman B's. One day, A & B work together for 8 hrs, then B due to injury stops and A finishes the rest of the job in 2 hrs. How long would it take B to complete the job alone? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Workman A's rate of doing work is twice that of Workman B's.
One day, A & B work together for 8 hrs, then B due to injury stops and A finishes the rest of the job in 2 hrs.
How long would it take B to complete the job alone?
:
let a = time required by A to do the job
He works twice a fast as B, therefore
let 2a = time required by B to do the same job
let the completed job = 1
:
A works a total of 10 hrs, B works 8 hrs
The shared work equation + = 1
Multiply equation by 2a, cancel the denominators and you have:
2(10) + 8 = 2a
20 + 8 = 2a
28 = 2a
a = 14 for A to do the job alone
then
2(14) = 28 hrs for B to do the job alone
:
;
See if that works out using decimals + = 1
.7143 + .2857 = 1