If a boatman can row upstream at 10 km/h and downstream at 12 km/h, then find the ratio of the speed of the boat in still water and the speed of the current.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e 11 : 1.
Upstream = u − v = 10, Downstream = u + v = 12
⇒ 2u = 22 ⇒ u = 11; v = 1
Required ratio (boat in still water : current) = 11 : 1