Question 654457
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If A takes 6 days at 7 hours per day, then she works 42 hours to complete the job.  That means she completes *[tex \LARGE \frac{1}{42}]nd of the job in one hour.  Likewise B completes *[tex \LARGE \frac{1}{56}]th of the job in one hour.


Together they complete *[tex \LARGE \frac{1}{42}\ +\ \frac{1}{56}]


Add these two fractions to get the fraction of the job the two of them complete in one hour working together.  Take the reciprocal to get the number of hours it takes the two of them to complete the job.  Divide that number of hours by 8 to get the number of 8 hour days.


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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