Question

A boat which has a speed of 5 km/hr in still water crosses a river of width 1 km along the shortest possible path in 15 minutes. The velocity of the river water (in km/hr) is

(a) 1 (b) 3 (c) 4 (d) √41

Answer 1

(b) The speed of the boat along the shortest possible path

Now the velocity of the riverwater