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The rate at which he rows in still water isA man rows down a river 15 km in 3 hrs. with the stream and returns in 7 1 hrs, 2
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- 2.5 km/hr
- 1.5 km/hr
- 3.5 km/hr
- 4.5 km/hr
- 2.5 km/hr
Correct Option: C
Let speed of person in still water = p kmph and speed of current = q kmph
∴ p + q = | = 5 kmph ........( 1 ) | |
3 |
& p – q = | ||||
2 |
p - q = 2 kmph ......( 2 )
On adding equations ( 1 ) and ( 2 ) ,
2p = 7 ⇒ p = | = 3.5 kmph | |
2 |
We can find the required answer with the help of given formula : :
Here, p = | = 5 kmph | |
3 |
q = | ||||
2 |
q = 2 km/hr
Speed of Boat = | (p + q) | |
2 |
Speed of Boat = | (5 + 2) = 3.5 kmph | |
2 |