$A$ man can row $20 \text{ km/h}$ in still water and the speed of the stream is $5 \text{ m/s}$. The ratio of the speed of the man to the speed of the current is:

$A$ boatman rows $1\, km$ in $5\, min$ along the stream and $6\, km$ in $1\, h$ against the stream. The speed of the stream is $km/h$.

$A$ 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:

$A$ boat goes $6\, km$ upstream and back again to the starting point in $2\, hours$. If the velocity of the stream is $4\, km/hr$,what is the speed of the boat in still water? (in $km/hr$)

$P, Q, R$ are three towns on a river which flows uniformly. $Q$ is equidistant from $P$ and $R$. $A$ man rows from $P$ to $Q$ and returns in $10 \, h$. He can row from $P$ to $R$ in $4 \, h$. The ratio of the speed of the man in still water to the speed of the current is

Speed of a man is $10 \text{ km/h}$ in still water. If the rate of current is $3 \text{ km/h}$,then the effective speed of the man upstream is ....... $\text{km/h}$.