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प्रश्न
A and B together can do a piece of work in `6 2/3` days, but B alone can do it in 10 days. How long will A take to do it alone?
उत्तर
A and B can do the work in =`6 2/3` days = `20/3` days
B can do the work in = 10 days
∴ (A + B)'s 1-day work =`3/20`
B's 1-day work =`1/10`
A's 1-day work =`3/20-1/10`
`=(3-2)/20=1/20`
∴ A can do the work in = 20
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