Keshav can row 60 km downstream and 36 km upstream, taking 10 h each time. What is the velocity of the current?

Speed upstream = Distance/Time = 60/10 = 6 km/h
Speed upstream = Distance/Time = 36/10 = 3.6 km/h
∴ Velocity of the current = (speed downstream - Speed upstream)/2
= (6 - 3.2)/2 = 1.2 km/h