If a $200 \, m$ long train crosses a platform of the same length as that of the train in $20 \, s$,then the speed of the train is (in $km/hr$).

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 $km$)

$A$ 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 $\text{km}$)

Walking at $3 \, km/h$,Pintu reaches his school $5 \, minutes$ late. If he walks at $4 \, km/h$,he will be $5 \, minutes$ early. The distance of Pintu's school from his house is (in $km$):

$A$ car travels a distance of $75 \, km$ at the speed of $25 \, km/h$. It covers the next $25 \, km$ of its journey at the speed of $5 \, km/h$ and the last $50 \, km$ of its journey at the speed of $25 \, km/h$. What is the average speed of the car? (in $km/h$)

$A, B$ and $C$ can walk at the rates of $3, 4$ and $5 \text{ km/h}$ respectively. They start from Pune at $1, 2$ and $3 \text{ o'clock}$ respectively. When $B$ catches $A$,$B$ sends him back with a message to $C$. When will $C$ get the message?