Correct Answer - Option 1 : 1.2 km/hr
Given
Downstream distance = 30 km
Upstream distance = 18 km
Formula Used
Distance = speed × time
velocity of current = [(downstream speed) - (upstream speed)]/2
Calculation
Speed of downstream = 30/5 = 6 km/hr
Speed of Upstream = 18/5 = 3.6 km/hr
Velocity of stream = (6 - 3.6)/2 = 1.2 km/hr
∴ The speed of current is 1.2 km/hr
