$A$ man travels a distance of $24 \, km$ at $6 \, km/h$,another distance of $24 \, km$ at $8 \, km/h$,and a third distance of $24 \, km$ at $12 \, km/h$. His average speed for the whole journey (in $km/h$) is?

Two trains,each of length $125 \, m$,are running on parallel tracks in opposite directions. One train is running at a speed of $65 \, km/h$ and they cross each other in $6 \, s$. The speed of the other train is (in $km/h$):

$A$ 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 $m$)

The distance between two cities $A$ and $B$ is $330 \, km$. $A$ train starts from $A$ at $8 \, a.m.$ and travels towards $B$ at $60 \, km/hr$. Another train starts from $B$ at $9 \, a.m.$ and travels towards $A$ at $75 \, km/hr$. At what time do they meet?

If $I$ walk at $5\, km/hr$,$I$ miss a train by $7\, minutes$. However,if $I$ walk at $6\, km/hr$,$I$ reach the station $5\, minutes$ before the departure of the train. The distance between my house and the station is (in $km$)

In a race of $800\, m,$ $A$ can beat $B$ by $40\, m$. In a race of $500\, m,$ $B$ can beat $C$ by $5\, m$. In a race of $200\, m,$ $A$ will beat $C$ by? (in $m$)