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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?
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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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संबंधित प्रश्न
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What part of work will be left, after they have worked together for 2 days?
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(ii) How much work is still left?
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| S.No | Speed | Distance | Time (Hours) |
| i | 35 Km/hour | 280 Km | |
| ii | 40 Km/hour | 360 Km | |
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| iv | 50 Km/hour | 300 Km | |
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Speed of the boat (how far it goes in one hour) |
| Log boat | 20 | 4 km per hour |
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