Upstream speed and downstream speed of a boat is 15 km/hr and 25 km/hr respectively. What is the difference (in km/hr) between the speed of boat in still water and the speed of stream?
Show answer & explanation
Correct answer: B
Explanation
Speed of the boat = (25 + 15) / 2 = 20 km/hr
Speed of the stream = (25 - 15) / 2 = 5 km/hr
Difference = 20 - 5 = 15 km/hr