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

$A$ man can row $7 \frac{1}{2} \, km/hr$ in still water. If in a river running at $1.5 \, km/hr$,it takes him $50 \, minutes$ to row to a place and back,how far off is the place? (in $km$)

$A$ river is flowing with a steady speed of $4\, km/h$. One rows his boat downstream in the river and then returns by rowing upstream in the same river. When he returns to the starting point,the total distance covered by him is $42\, km$. If the return journey takes $2\, h$ more than his outward journey,then the speed of his rowing in still water must be (in $km/h$)

$A$ man can row $6 \, km/h$ in still water. If the speed of the current is $2 \, km/h$,it takes $3 \, h$ more in upstream than in the downstream for the same distance. The distance is......$km$.

$A$ man takes $3$ $hours$ $45$ $minutes$ to row a boat $15 \; km$ downstream of a river and $2$ $hours$ $30$ $minutes$ to cover a distance of $5 \; km$ upstream. Find the speed of the river current in $km/hr$.

The speed of a boat in still water is $4 \, km/h$ and the speed of the current is $2 \, km/h$. If the time taken to reach a certain distance upstream is $9 \, hours$,find the time it will take to go the same distance downstream (in $hrs$).