Aman takes half the time rowing a certain distance downstream than upstream.
Statement (I): Ratio of the speed of the boat in still water to the speed of the water current is 2:1.
Statement (II): If the speed of the boat in still water is 6 km per hour, then the speed of the water current is 2 km per hour.
Choose the most appropriate answer from the options given below.

Let the upstream and downstream distances be D. Let the speed of the boat in still water be B, and the speed of the current be R.

Aman takes half the time rowing a certain distance downstream than upstream.

$$\dfrac{D}{B+R}=\dfrac{1}{2}\times\dfrac{D}{B-R}$$

$$2B-2R=B+R$$

$$B=3R$$

Statement I

Ratio of speed of boat in still water to the speed of current = B:R = 3R:R = 3:1

Thus, statement I is FALSE

Statement II

Speed of boat in still water (B) = 6 km/h

Speed of river (R) = B/3 = 6/3 = 2 km/h

Thus, statement II is TRUE