A man can row 5 kmph in still water. If the the river is running at 1 kmph, it takes him 75 minutes to row to a place and back. How far is the place?
3 km
2.5 km
2 km
8.5 km
4 km
Let's assume distance = D
Upstream Speed = 5 - 1 => 4
Downstream Speed = 5 + 1 => 6
75 minutes in hours = 5/4 hours
According to question,
D/4 + D/6 = 5/4
5D/12 = 5/4
D = 3 KM