Question

Find the difference in time taken by the boat travelling at 25 km/hr to cover 60 km while travelling upstream and downstream. Speed of the stream is 5 km/hr?

• A. 60 minutes
• B. 30 minutes
• C. 90 minutes
• D. 40 minutes

Answer 1

Answer:

A. 60 minutes

Speed of stream = 5 km/hr

Speed of the boat upstream = Speed of Boat- Speed of Stream = (25-5)km/hr = 20 km/hr

Speed of the boat downstream =Speed of Boat+ Speed of Stream = (25+5)km/hr = 30 km/hr

distance = 60 km

Time taken to cover Upstream Distance=$\frac{60}{20}$=3 hr

Time taken to cover Downstream Distance=$\frac{60}{30}$ = 2 hr

Time Difference = 3 - 2 = 1 hr= 60 minutes.