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A Can Do a Piece of Work in 6 Days and B Can Do It in 8 Days. How Long Will They Take to Complete It Together?

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Question

A can do a piece of work in 6 days and B can do it in 8 days. How long will they take to complete it together?

Sum
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Solution

A can do a work in = 6 days

∴ A's one day's work = `1/6`

B can do the same work in = 8 dyas

∴ B is one day's work = `1/8`

∴ A ad B's both one day's work

`= 1/6 + 1/8 = (4 + 3)/24 = 7/24`

∴ Both A and B can do the same work in `24/7 = 3 3/7` days

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

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Selina Concise Mathematics [English] Class 7 ICSE
Chapter 7 Unitary Method (Including Time and Work)
Exercise 7 (C) | Q 1

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