Question

A man swims 320 m against the water current in 4 minutes. In still water, he is able to swim with a speed 5 times that of the current. Calculate the speed of the current, in m/min.

Answer 1

Let the speed of the current is x m/min and speed of the man is y.

The man swims 320 m against the water current in 4 minutes.

i.e., y - x = 320/4 = 80 m/min .....(1)

again, The man is able to swim with a speed 5 times that of current.

i.e., y = 5x..........(2)

from equation (1) and (2),

5x - x = 80 m/min

or, 4x = 80 m/min

or, x = 20m/min

hence, the speed of the current is 20m/min