$A$ 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 bus fare for one person is $Rs. 420$ from Agra to Aligarh and the train fare between the same places for one person is equal to $\frac{3}{4}$ of the bus fare for $2$ persons between the same places. What is the total fare paid by $2$ persons traveling by bus and $4$ persons traveling by train between the two places? (in $Rs.$)

$A$ train covers a distance between station $A$ and station $B$ in $45 \, min$. If the speed of the train is reduced by $5 \, km/h$,then the same distance is covered in $48 \, min$. The distance between stations $A$ and $B$ is? (in $km$)

$A$ hare sees a dog $100\, m$ away from her and runs off in the opposite direction at a speed of $12\, km/h$. $A$ minute later,the dog perceives her and gives chase at a speed of $16\, km/h$. How much distance is covered by the hare after being spotted? (in $m$)

$A$ train $800 \, m$ long is running at a speed of $78 \, km/h$. If it crosses a tunnel in $1 \, minute$,then the length of the tunnel (in $m$) is:

The wheel of an engine is $3 \frac{3}{4}$ metres in circumference and makes $4$ revolutions in $2$ seconds. The speed of the train is (in $km/h$):