$A$ man on tour travels the first $160 \, km$ at $64 \, km/hr$ and the next $160 \, km$ at $80 \, km/hr$. What is the average speed for the first $320 \, km$ of the tour (in $km/hr$)?

The ratio between the speed of a train and a car is $16: 15$. Also,a bus covered a distance of $480 \, km$ in $8 \, hours$. The speed of the bus is $\frac{3}{4}$ the speed of the train. How much distance will the car cover in $6 \, hours$? (in $km$)

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:

$A$ man travelled a distance of $80\, km$ in $7\, hours$,partly on foot at the rate of $8\, km/h$ and partly on bicycle at $16\, km/h$. The distance travelled on foot is (in $km$):

$A$ bus travels $720 \text{ km}$ in $20 \text{ hours}$. Calculate its average speed in $\text{metres/seconds}$.

If the length of the train is $700 \, m$ and the length of the platform is $500 \, m$,find the time taken by the train moving at $54 \, km/h$ to cross the platform (in $sec$).