The velocity of a boat in still water is 9 km/hr, and the speed of the stream is 2.5 km/hr. How much time will the boat take to go 9.1 km against the stream?
Answer with explanationAnswer: Option D
Answer with the Explanation:
Speed of boat in still water (Sb) = 9km/hr Speed of stream (Sc) = 2.5km/hr Distance against the stream = 9.1 km
Note: against the steam = upstream
Now, apply the formula:
The speed of boat upstream = speed of boat – the speed of the stream
The speed of upstream = 9-2.5 = 6.5km/hr Now, time= Distance/speed Time = 9.1/6.5, or 7/5 Or, time = 1[2/5] Or, 1hr + (2/5)*60 = 1hr + 24minutes