A river 100m wide is running downwards at the rate of 1 km per hour and a swimmer who can swim at the rate of 3.6 km/hr wishes to reach a point just opposite. Along which direction should he strike and how long will he take to cross the river?

### Asked by Topperlearning User | 4th Jun, 2014, 01:23: PM

Let the swimmer swim at an angle ÃŽÂ¸ as shown in the figure to reach the point B directly opposite to A.

### Answered by | 4th Jun, 2014, 03:23: PM

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