Buses start from a bus terminal with a speed of $20 \text{ km/h}$ at intervals of $10 \text{ mins}$. What is the speed of a man coming from the opposite direction towards the bus terminal if he meets the buses at intervals of $8 \text{ mins}$? (in $\text{km/h}$)

$A$ man travelled a certain distance by train at the rate of $25 \text{ km/h}$ and walked back at the rate of $4 \text{ km/h}$. If the whole journey took $5 \text{ h } 48 \text{ min}$,what is the distance? (in $\text{km}$)

$A$ person travels from $P$ to $Q$ at a speed of $40 \, km/hr$ and returns by increasing his speed by $50 \%$. What is his average speed for both the trips? (in $km/hr$)

$A$ man covered a certain distance at some speed. Had he moved $3 \text{ km/hr}$ faster,he would have taken $40 \text{ minutes}$ less. If he had moved $2 \text{ km/hr}$ slower,he would have taken $40 \text{ minutes}$ more. The distance (in $\text{km}$) is:

The speed of a car increases by $2\, km/h$ after every hour. If the distance travelled in the first hour was $35\, km$,what is the total distance travelled in $12$ hours? (in $km$)

$A$ thief is spotted by a policeman from a distance of $400\, m$. When the policeman starts the chase,the thief also starts running. Assuming the speed of the thief is $5\, km/h$ and that of the policeman is $9\, km/h$,how far will the thief have run before he is overtaken by the policeman? (in $m$)