A man takes twice as long to row a distance against the stream as to row the same distance in favour of the stream. The ratio of the speed of the boat (in still water) and the stream is:

Solution (By Examveda Team)

Let man's rate upstream be x kmph
Then, his rate downstream = 2x kmph
∴ (speed in still water) : (Speed of stream)
$$\eqalign{ & = {\frac{{2x + x}}{2}} : {\frac{{2x - x}}{2}} \cr & = \frac{{3x}}{2}:\frac{x}{2} \cr & = 3:1 \cr} $$