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सी.आई.एस.सी.ई.आईसीएसई ICSE Class 7

A and B Working Together Can Do a Piece of Work in 10 Days B Alone Can Do the Same Work in 15 Days. How Long Will a Alone Take to Do the Same Work ?

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प्रश्न

A and B working together can do a piece of work in 10 days B alone can do the same work in 15 days. How long will A alone take to do the same work?

योग
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उत्तर

A and B working together can do a piece of work in 10 days

and B alone can do the same work in 15 days

A and B's one day's work = `1/10`

and B's one day's work = `1/15`

∴ A's one day's work = `1/10 - 1/15`

`= (3 - 2)/30 = 1/30`

Hence A can do the same work in = 30 days

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अध्याय 8: Unitary Method (Including Time and Work) - Exercise 7 (C)

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आर.के. बंसल Concise Mathematics [English] Class 7 ICSE
अध्याय 8 Unitary Method (Including Time and Work)
Exercise 7 (C) | Q 2

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