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A and B Together Can Do a Piece of Work in 6 2/3 Days, but B Alone Can Do It in 10 Days. How Long Will a Take to Do It Alone? - Mathematics

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Question

A and B together can do a piece of work in `6 2/3` days, but B alone can do it in 10 days. How long will A take to do it alone?

Sum
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Solution

A and B can do the work in =`6 2/3` days = `20/3` days

B can do the work in = 10 days

∴ (A + B)'s 1-day work =`3/20`

B's 1-day work =`1/10`

A's 1-day work =`3/20-1/10`

`=(3-2)/20=1/20`

∴ A can do the work in = 20 

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Chapter 10: Direct and Inverse Variations - Exercise 10 (E) [Page 133]

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Selina Concise Mathematics [English] Class 8 ICSE
Chapter 10 Direct and Inverse Variations
Exercise 10 (E) | Q 2 | Page 133

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