$A$ boatman can row $48\, km$ downstream in $4\, hours$. If the speed of the current is $5\, km/h$,then find in what time will he be able to cover $8\, km$ upstream? (in $hours$)

Speed of a boat is $5 \, km/h$ in still water and the speed of the stream is $3 \, km/h$. If the boat takes $3 \, h$ to go to a place and come back,the distance of the place is ....... $km$.

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 covers $12\, km$ upstream and $18\, km$ downstream in $3\, hours,$ while it covers $36\, km$ upstream and $24\, km$ downstream in $6\frac{1}{2}\, hours.$ What is the speed of the current? (in $km/h$)

$A$ boat takes $90$ minutes less to travel $36$ miles downstream than to travel the same distance upstream. If the speed of the boat in still water is $10$ miles/hour,the speed of the stream is.......miles/hour.