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प्रश्न
A and B working together can do a piece of work in 10 days B alone can do the same work in 15 days. How long will A alone take to do the same work?
उत्तर
A and B working together can do a piece of work in 10 days
and B alone can do the same work in 15 days
A and B's one day's work = `1/10`
and B's one day's work = `1/15`
∴ A's one day's work = `1/10 - 1/15`
`= (3 - 2)/30 = 1/30`
Hence A can do the same work in = 30 days
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