SOLUTION: Jerry worked for one day on a project that he could have completed alone in nine days. Bill joined Jerry the next day, and they worked together for exactly three days to complete

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Question 120561: Jerry worked for one day on a project that he could have completed alone in nine days. Bill joined Jerry the next day, and they worked together for exactly three days to complete the project. How much of the job did Bill do in those three days? Express you answer as a common fraction.
Bill worked 3 out of 4 days, but it could have been done in 9 days which would be 8 out of 9 days for Bill if he was working alone. Jerry worked 1 day out of 4 and 1 day out of 9 possible days.
3/4 x 8/9 = 24/36 = 2/3
I say the answer is 2/3 for how much of the work Bill did.

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Jerry worked for one day on a project that he could have completed alone in nine days. Bill joined Jerry the next day, and they worked together for exactly three days to complete the project. How much of the job did Bill do in those three days? Express you answer as a common fraction.
:
I would do it this way:
:
Let the completed job = 1
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WE know Jerry's share = 4/9 (he worked 4 days)
Let Bills share = 3/x (he worked 3 days)
:
4%2F9 + 3%2Fx = 1
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Multiply equation by 9x to get rid of the denominators
9x*4%2F9 + 9x*3%2Fx = 9x(1)
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Cancel out the denominators and we have:
4x + 9(3) = 9x
:
27 = 9x - 4x
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27 = 5x
:
x = 27/5
:
x = 5.4
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Bills fraction: 3%2F5.4 = 30%2F54 = 5%2F9 is Bill's share of the work
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We can check that
(4/9) + (5/9) = 1, the completed job