Question

The speed of boat in still water is 25 kmph and the downstream speed of boat is 35kmph. In what time boat can travel 30km upstream?

1. 2.5 hours
2. 4 hours
3. 1.5 hours
4. 2 hours
5. 1 hour

Answer 1

Correct Answer - Option 4 : 2 hours

Given:

⇒ Speed of boat in still water = 25 kmph

⇒ Speed downstream = 35kmph

⇒ Speed of stream = 35 - 25 = 10 kmph

⇒ Speed upstream = 25 - 10 = 15kmph

∴ Required time = 30/15 = 2 hours