Question

A swimmer can swim a distance of 36 kilometers in the direction of water current in the same time it takes to swim 36 kilometers in the opposite direction of water current in the stream. If in still water the swimmer has a speed of 12 kilometers per hour more than the speed of the water in the stream, then what is the speed of the water?

a) 6 km/h
b) 8 km/h
c) 10 km/h
d) 12 km/h

Answer 1

The speed of the water current is 0 km/h.

Step-by-step explanation:

In this problem, the swimmer can cover a distance of 36 kilometers in the same time when swimming with the current and against the current. Let's say the speed of the water current is 'x' km/h. In still water, the swimmer's speed is 12 km/h more than the speed of the water current, which can be expressed as (x + 12) km/h.

When swimming with the current, the effective speed can be written as (x + 12 + x) km/h = (2x + 12) km/h. Similarly, when swimming against the current, the effective speed can be written as (x + 12 - x) km/h = 12 km/h. Since the distances covered are the same, we can set up the equation:

36 / (2x + 12) = 36 / 12

Simplifying, we get:

2x + 12 = 12

2x = 0

x = 0

Therefore, the speed of the water current is 0 km/h.