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सी.आई.एस.सी.ई.आयसीएसई ICSE Class 7

A and B Take 6 Hours and 9 Hours Respectively to Complete a Work. a Works for 1 Hour and Then B Works for Two Hours. - Mathematics

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प्रश्न

A and B take 6 hours and 9 hours respectively to complete a work. A works for 1 hour and then B works for two hours.
(i) How much work is done in these 3 hours?
(ii) How much work is still left?

बेरीज
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उत्तर

A takes 6 hours to finish work

and B take 9 hours to finish the same work

∴ A's 1 hour's work = `1/6`

and B's 1 hour's work = `1/9`

and B's 2 hours work =`1/9 xx 2= 2/9`

(i) Now A's 1 hours work + B's 2 hours work

`= 1/6 + 2/9 = (3 + 4)/18 = 7/18`

(ii) Work left = `1 - 7/18 = (18 - 7)/18 = 11/18`

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

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सेलिना Concise Mathematics [English] Class 7 ICSE
पाठ 7 Unitary Method (Including Time and Work)
Exercise 7 (C) | Q 4

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