The current of a stream runs at the rate of $4 \text{ km/h}$. $A$ boat goes $6 \text{ km}$ and comes back to the starting point in $2 \text{ hours}$. The speed of the boat in still water is ....... $\text{km/h}$.

When the speed of a boat in still water is $4\, km/h$ and the rate of stream is $2\, km/h$,find the upstream speed of the boat (in $km/h$).

$A$ boat running upstream takes $8$ $hours$ $48$ $minutes$ to cover a certain distance,while it takes $4$ $hours$ to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the current respectively?

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 $\text{km/h}$.

$A$ man can row against the current $\frac{3}{4}$ of a kilometre in $15$ minutes and returns the same distance in $10$ minutes. The ratio of his speed to that of the current is

$A$ 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.