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It takes Nina 6 hours to proof a chapter of Hawkes Learning Systems' College Algebra book and it takes Mandy 2 hours. How long would it take them working together? (Round your answer to two decimal places.)

User Technupe
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1 Answer

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Time taken by Nina to complete the chapter = was 6 hours.

Amount of chapter completed in 1 hour = 1/6.


(1)/(2)

Mandy takes the time to complete the chapter = 2 hours.

Amount of chapter completed in 1 hour = 1/2.

Amount of chapters completed by both in 1 hour is calculated as,


\begin{gathered} For\text{ 1 hour = }(1)/(6)+(1)/(2) \\ For\text{ 1 hour = }(1)/(6)_+(3)/(6) \\ For\text{ 1 hour = }(4)/(6)\text{ = }(2)/(3) \end{gathered}

Thus the amount of time taken by both of them to complete the chapter is


(3)/(2)\text{ hours or 1.5 hours}

User Chirag Dasani
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