Question 1159099
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If it takes person A *[tex \Large x] time periods to complete one job, then person A can complete *[tex \Large \frac{1}{x}] of the job in one time period.  Likewise person B who can complete one job in *[tex \Large y] time periods, can complete *[tex \Large \frac{1}{y}] of the job in one time period.


Working together, A and B can complete:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \frac{1}{x}\ +\ \frac{1}{y}\ =\ \frac{x\,+\,y}{xy}]


of one job in one time period, which is to say they can complete one job in:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \frac{xy}{x\,+\,y}]


time periods. So working together, they can complete *[tex \Large J] complete jobs in:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ J\,\cdot\,\frac{xy}{x\,+\,y}]
								
								
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
<img src="http://c0rk.blogs.com/gr0undzer0/darwin-fish.jpg">
*[tex \Large \ \
*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
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