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प्रश्न
A is able to complete `1/3` of a certain work in 10 hrs and B is able to complete `2/5` of the same work in 12 hrs. Find:
(i) how much work can A do in 1 hour ?
(ii) how much work can B do in 1 hour ?
(iii) in how much time will the work be completed, if both work together.
उत्तर
A can do `1/3` of work in = 10 hours
∴ A can do full work in `= (10 xx 3)/1 = 30` hours
B can do `2/5` of the work in = 12 hours
∴ B can do the whole work in =`(12 xx 5)/2` = 30 hours
(i) Now A's 1 hour's work = `1/30`
(ii) B's 1 hours work = `1/30`
(iii) Both's 1 hour's work
`=1/30 + 1/30 = 2/30 = 1/15`
∴ Both can finish the work in 15 hours
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संबंधित 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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| Type of boat | Catch of fish in one trip (in kg) |
Speed of the boat (how far it goes in one hour) |
| Log boat | 20 | 4 km per hour |
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| Motorboat | 800 | 20 km per hour |
| Machine boat | 6000 | 22 km per hour |
