Question

If the speed of a boat in still water is 25 km/h and the speed of the current is 10 km/h. Find the time taken by a boat to travel 105 km with the current.
1. 5 hours
2. 4 hours
3. 2 hours
4. 3 hours
5. 6 hours

Answer 1

Correct Answer - Option 4 : 3 hours

Given:

Speed of a boat in still water = 25 km/h 

and the speed of the current = 10 km/h.

Formula used:

Time = distance/speed

Calculation:

distance travelled = 105 km

downstream speed = (25 + 10)

⇒ 35 km/h

Time = 105/35

⇒3 hours

∴ Time taken by boat to travel 105 km with current  is 3 hours.