The speed of a boat in still water is 9 km/hr and the speed of stream is 3 km/hr. The difference between the upstream speed and downstream speed will be:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 6 km/hr.
Downstream speed = speed in still water + speed of the stream
⇒ DS = 9 + 3
⇒ 12
Upstream speed = speed in still water - speed of the stream
⇒ DS = 9 - 3
⇒ 6
⇒ 12 - 6 = 6 km/h