Speed of a man is $10 \text{ km/h}$ in still water. If the rate of current is $3 \text{ km/h}$,then the effective speed of the man upstream is ....... $\text{km/h}$.

Two boats $A$ and $B$ start towards each other from two places,$108 \text{ km}$ apart. The speeds of boats $A$ and $B$ in still water are $12 \text{ km/h}$ and $15 \text{ km/h}$,respectively. If $A$ proceeds down the stream and $B$ proceeds up the stream,they will meet after .......... $\text{h}$.

The speed of a boat in still water is $6\, km/hr$ and the speed of the stream is $1.5\, km/hr$. $A$ man rows to a place at a distance of $22.5\, km$ and comes back to the starting point. The total time taken by him is

If a boat goes upstream at a speed of $21\, km/h$ and comes back the same distance at $28\, km/h$,what is the average speed (in $km/h$) for the total journey?

$A$ man can row $7\, km/hr$ in still water. If the river is running at $3\, km/hr$,it takes $6\, hours$ more to row upstream than to row downstream for the same distance. How far is the place? (in $km$)

The speed of a boat in still water is $8\, km/h$. If its speed downstream is $15\, km/h$,then the speed of the stream is $.......\, km/h$.