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A motorboat in still water travels at a speed of 36 kmph. It goes 56 km upstream in 1 hour 45 minutes. The time taken by it to cover the same distance down the stream will be :
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- 2 hours 25 minutes
- 3 hours
- 1 hour 24 minutes
- 2 hours 21 minutes
- 2 hours 25 minutes
Correct Option: C
As per the given in question ,
| Speed of the motorboat upstream = | ||||
| 1 | ||||
| 4 | hours | |||
| Speed of the motorboat upstream = | = 32 kmph | |
| 7 |
Let the speed of the current be y kmph
∴ 36 – y = 32
⇒ y = 36 – 32 = 4 kmph
Speed of motor boat downstream = 36 + 4 = 40 kmph
| ∴ Time taken to cover 56 km at 40 kmph = | = | hours or 1 hour 24 minutes | ||
| 40 | 5 |
