The speed of boat in still water is 20 km/hr. If it travels 26 km downstream and 14 km upstream in same time, what is the speed of the stream?
Answer: C
Let X be speed of stream
Speed of boat downstream = (20 + X )
Speed of boat upstream = (20 – X)
It is given that boat takes same time to travel 26 km downstream and 14 km upstream
[26/(20 +X)] = [14 / (20 – X)]
520 – 26 X = 280 + 14X
40X = 240
X = 6 km/hr