A man can swim 4 km in still water in 10 min. If the speed of the stream is 11.5 km/hr, in how much time will he swim 6 km upstream and return back?
1
27 min.
2
30 min.
3
33 min.
4
36 min.
5
39 min.
A man can swim 4 km in still water in 10 min. If the speed of the stream is 11.5 km/hr, in how much time will he swim 6 km upstream and return back?