If a man's rate with the current is $12\, km/h$ and the rate of current is $1.5\, km/h$,then the man's rate against the current in $km/h$ is...........

Rahul can travel $12 \text{ miles}$ downstream in a certain river in $6 \text{ hours}$ less than it takes him to travel the same distance upstream. But if he could double his usual rowing rate for his $24 \text{ mile}$ round trip,the downstream $12 \text{ miles}$ would take only one hour less than the upstream $12 \text{ miles}$. What is the speed of the current in $\text{miles/hour}$?

$A$ boat travels upstream from $B$ to $A$ and downstream from $A$ to $B$ in $3$ $hrs$. If the speed of the boat in still water is $9$ $km/h$ and the speed of the current is $3$ $km/h$,the distance between $A$ and $B$ is......$km$.

$A$ 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.

$A$ man can row upstream $36 \text{ km}$ in $6 \text{ hours}$. If the speed of a man in still water is $8 \text{ km/hr}$,find how much distance he can cover downstream in $10 \text{ hours}$? (in $\text{km}$)

$A$ boat covers $24 \, km$ upstream and $36 \, km$ downstream in $6 \, hours,$ while it covers $36 \, km$ upstream and $24 \, km$ downstream in $6 \frac{1}{2} \, hours.$ Then the velocity of the current is..........$km/h$