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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.
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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 can do a piece of work in 4 days and B can do the same work in 5 days. Find, how much work can be done by them working together in:
- one day
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What part of work will be left, after they have worked together for 2 days?
Two taps can fill a cistern in 10 hours and 8 hours respectively. A third tap can empty it in 15 hours. How long will it take to fill the empty cistern, if all of them are opened together?
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| S.No | Speed | Distance | Time (Hours) |
| i | 35 Km/hour | 280 Km | |
| ii | 40 Km/hour | 360 Km | |
| iii | 45 Km/hour | 315 Km | |
| iv | 50 Km/hour | 300 Km | |
| v | 55 Km/hour | 275 Km |
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In one trip the logboat brings about 20 kg of fish. But other types of boats bring a bigger catch as given in the table. The table also shows the speed of each type of boat, which is how far each boat goes in one hour. Look at the table and calculate -
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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 |
| Long tail boat | 600 | 12 km per hour |
| Motorboat | 800 | 20 km per hour |
| Machine boat | 6000 | 22 km per hour |
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