$A$ 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 $\text{km}$)

The speed of a boat in still water is $9\, km/h$ and the speed of the stream is $1.5\, km/h$. $A$ man rows to a place at a distance of $105\, km$ and comes back to the starting point. What is the total time taken by him?

In a fixed time,a boy swims double the distance along the current that he swims against the current. If the speed of the current is $3 \text{ km/h}$,then find the rate of swimming in still water in $\text{km/h}$.

On a river,$Q$ is the midpoint between two points $P$ and $R$ on the same bank. $A$ boat can travel from $P$ to $Q$ and back in $12$ hours,and from $P$ to $R$ in $16$ hours $40$ minutes. How long would it take to travel from $R$ to $P$? (in hours)

$A$ boat travels $32 \ km$ downstream in $4 \ hours$ and $24 \ km$ upstream in $6 \ hours$. What is the speed (in $km/hr$) of the boat in still water?

$A$ boat travels $2\, km$ upstream in a stream flowing at $3\, km/h$ and then returns downstream to the starting point in $30\, minutes$. The speed of the boat in still water is........$km/h$.