$A$ boatman can row $2\, km$ against the stream in $20\, minutes$ and return in $18\, minutes.$ Find the rate of the current in $km/h$.

$A$ person takes total $5$ $hours$ to go to a destination downstream and come back upstream by boat. If the speed of the boat in still water is $10 \text{ km/h}$ and the speed of the stream is $4 \text{ km/h}$,what is the distance of the destination from the starting point (in $\text{km}$)?

$A$ boatman takes twice as long to row a distance against the stream as to row the same distance with the stream. Find the ratio of the speed of the boat in still water to the speed of the stream.

$A$ boat goes $14 \ km$ upstream in $42 \ minutes$. The speed of the stream is $4 \ km$. The speed of the boat in still water 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:

$A$ swimmer's speed in downstream is $11 \, km/h$ and speed of the stream is $1.5 \, km/h$. Find the upstream speed of the swimmer? (in $km/h$)