A boat running downstream covers 24 km’s in 4 hours while for covering the same distance upstream it takes 6 hours whats the speed of the boat in still water?

A boat running downstream covers 24 km’s in 4 hours while for covering the same distance upstream it takes 6 hours whats the speed of the boat in still water?

A. 3.5km/hr
B. 5.5 km/hr
C. 6 km/hr
D. Data Inadequate
E. None of these
Explanation:
Speed downstream = 24/4 km/hr = 6 km/hr
Speed upstream = 24/6 km/hr = 4 km/hr
Speed of the boat in still water = ½ (6 +4)km/hr = 5 km/hr