Speed of a boat downstream and upstream is 42 km/hr and 36 km/hr respectively. What is the speed (in km/hr) of the boat in still water?
Show answer & explanation
Correct answer: B
Explanation
Speed of the boat in still water -
= (Speed downstream + Speed upstream) ÷ 2
= (42 + 36) ÷ 2
= 39 km/hr