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प्रश्न
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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उत्तर
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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