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A Can Do a Work in 15 Days and B in 20 Days. If They Together Work on It for 4 Days; What Fraction of the Work Will Be Left?

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Question

A can do a work in 15 days and B in 20 days. If they together work on it for 4 days; what fraction of the work will be left?

Sum
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Solution

A's 1-day work = `1/15`

B's 1-day work = `1/20`

(A+B)'s 1-day work =`1/15+1/20`

`=(4+3)/60=7/60`

(A+B)'s 4 days work =`7/60xx4=7/15`

Remaining work =`1-7/15=(15-7)/15`

`=8/15`

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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 3 | Page 133

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