A man can row at 5 km/hr in still water. If the velocity of current is 1 km/hr and it takes him 1 hour to row to a place and come back, how far is the place?

A man can row at 5 km/hr in still water. If the velocity of current is 1 km/hr and it takes him 1 hour to row to a place and come back, how far is the place?

A 2.4 km

B 2.5 km

C 3 km

D 3.6 km

E 2.0 km

Solution

Correct Answer: Option A

Speed downstream = (5 + 1) km/hr = 6 km/hr

Speed upstream = (5 − 1) km/hr = 4 km/hr

Let the required distance be x km.

Then,

⇒ (x/6) +(x/4) = 1

⇒ 2x + 3x = 12

⇒ 5x = 12

⇒ x = 2.4 km.