$A$ boat moves downstream at the rate of $1 \, km$ in $7 \frac{1}{2} \, \text{minutes}$ and upstream at the rate of $5 \, km/h$. What is the speed (in $km/h$) of the boat in still water?

$A$ man can row $44 \text{ km}$ downstream in $4 \text{ hours}$. If the man's rowing rate in still water is $8 \text{ km/hr}$,then find in what time will he cover $25 \text{ km}$ upstream? (in $\text{hours}$)

$A$ man can row $15\, km$ downstream in $3\, hours$ and $5\, km$ upstream in $2.5\, hours$. His speed in still water in $(km/hr)$ is:

$A$ 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 moves $20 \, km$ downstream in $5 \, hours$ and $10 \, km$ upstream in the same time. The speed of the stream is...........$km/h$.

In a stream running at $2 \, km/h$,a motorboat goes $10 \, km$ upstream and returns to the starting point in $55 \, min$. Find the speed of the motorboat in still water (in $km/h$).