In covering a distance of $30 \, km$,Abhay takes $2 \, hours$ more than Sameer. If Abhay doubles his speed,then he would take $1 \, hour$ less than Sameer. Abhay's speed is (in $km/h$):

$A$ person crosses a $600\, m$ long street in $5\, minutes$. What is his speed in $km/hr$?

$A$ person has to cover a distance of $6 \, km$ in $45 \, minutes$. If he covers one-half of the distance in two-third of the total time,to cover the remaining distance in the remaining time,his speed (in $km/hr$) must be:

How many $km/h$ does a man walk who passes through a street $600 \, m$ long in $5 \, minutes$?

Two trains,Kanpur Mail and Delhi Mail,start at the same time from stations Kanpur and Delhi respectively towards each other. After passing each other,they take $12\, \text{hours}$ and $3\, \text{hours}$ to reach Delhi and Kanpur respectively. If the Kanpur Mail is moving at the speed of $48\, \text{km/hr}$,the speed of the Delhi Mail is (in $\text{km/hr}$):

$A, B$ 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?