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it tastes Kim 11 hours to proof a chapter of Hawkes Learning System introductory algebra book and it takes Bethany 6 hours how long would it take then working together

User Pjehyun
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1 Answer

5 votes

Kim alone = 11 hours

Bethany alone = 6 hours

Let time for Kim and Bethany = t


\begin{gathered} (1)/(11)\text{ + }(1)/(6)\text{ = }(1)/(t) \\ \frac{6\text{ + 11}}{66}\text{ = }(1)/(t) \\ (17)/(66)\text{ = }(1)/(t) \\ \text{Cross multiply} \\ 17t\text{ = 66} \\ t\text{ = }(66)/(17) \\ t\text{ = 3}(15)/(17)\text{ hours} \end{gathered}

User Smitelli
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