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सी.आई.एस.सी.ई.आईसीएसई ICSE Class 7

A, B and C Together Finish a Work in 4 Days. If a Alone Can Finish the Same Work in 8 Days and B in 12 Days, Find How Long Will C Take to Finish the Work.

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प्रश्न

A, B and C together finish a work in 4 days. If A alone can finish the same work in 8 days and B in 12 days, find how long will C take to finish the work.

योग
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उत्तर

A. B and C finish work together in = 4 days.

A. B and C finish work together in 1 day = `1/4`

A' one day work = `1/8`

B's one day work = `1/12`

∴ C's one day work `= 1/4 - (1/8 + 1/12)`

`= (6 - (3 + 2))/24 = 1/24`

∴ C can finish the work in = 24 days

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

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सेलिना Concise Mathematics [English] Class 7 ICSE
अध्याय 7 Unitary Method (Including Time and Work)
Exercise 7 (C) | Q 11

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