$A$ man moves downstream at a rate of $14\, km/h$ and upstream at a rate of $6\, km/h$. The speed of the boat in still water is........$km/h$.

The current of a stream runs at $1 \, km/h$. $A$ motor boat goes $35 \, km$ upstream and back again to the starting point in $12 \, hours$. The speed of the motor boat in still water in $km/h$ is:

$A$ 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.

$A$ man can row at $5 \text{ km/hr}$ in still water. If the velocity of the current is $1 \text{ km/hr}$ and it takes him $1 \text{ hour}$ to row to a place and come back,how far is the place? (in $\text{km}$)

In a river,the ratio of the speed of the stream to the speed of a boat in still water is $2:5$. In another case,the ratio of the speed of the stream to the speed of a boat in still water is $3:4$. What is the ratio of the speeds of the first boat to the second boat in still water?

$A$ man rows a boat $18 \ km$ in $4 \ h$ downstream and returns upstream in $12 \ h$. The speed of the stream (in $km/h$) is