$A$ and $B$ are two towns. $A$ car goes from $A$ to $B$ at a speed of $64 \, km/h$ and returns to $A$ at a slower speed. If its average speed for the whole journey is $56 \, km/h$,find its return speed (in $km/h$).

An express train travelled at an average speed of $100 \, km/hr$, stopping for $3 \, minutes$ after every $75 \, km$. How long did it take to reach its destination $600 \, km$ from the starting point?

In what time will a train $100 \, m$ long cross an electric pole,if its speed is $144 \, km/h$? (in $seconds$)

The call rate of a $SIM$ of Company $A$ is one paisa for every three seconds. Another $SIM$ of Company $B$ charges $45 \text{ paisa per minute}$. $A$ man talked for $591 \text{ seconds}$ from the $SIM$ of Company $A$ and $780 \text{ seconds}$ from the $SIM$ of Company $B$. What would be the total amount he spent? (in $Rs.$)

$A$ car covers the first $39 \, km$ of its journey in $45 \, minutes$ and the remaining $25 \, km$ in $35 \, minutes.$ What is the average speed of the car (in $km/h$)?

If a train $110 \, m$ long passes a telegraph pole in $3 \, seconds$,then the time taken (in $seconds$) by it to cross a railway platform $165 \, m$ long is: