A person can swim in still water at 4 km/h. If the speed of water 2 km/h, how many hours will the man take to swim back against the current for 6km?
A. 3
B. 4
C. 4 (1/2)
D. Insufficient data
Explanation:
M = 4
S = 2
US = 4 – 2 = 2
D = 6
T = 6/2 = 3