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प्रश्न
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?
उत्तर
First tap can fill a cistern in 10 hours
Second tap can fill the cistern in 8 hours
Third tap can empty the cistern in 15 hours
∴ First tap's 1 hour's work = `1/10`
Second tap's 1 hour's work = `1/8`
and third tap's 1 hour's work = `1/15`
If all of them are opened together, then
heir one hour's work = `1/10 + 1/8 - 1/15`
`= (12 + 15 - 8)/120 = (27 - 8)/120 = 19/120`
∴ They can fill the cistren in =`120/19` hours
`= 6 6/19` hours
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Mohit can complete a work in 50 days, whereas Anuj can complete the same work in 40 days. Find:
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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:
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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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| 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 |
