$A$ $180 \, m$ long train crosses another $270 \, m$ long train running from the opposite direction in $10.8 \, s$. If the speed of the first train is $60 \, km/h$,what is the speed of the second train in $km/h$?

$A$ $100\, m$ long train passes a bridge at the rate of $72\, km/h$ in $25\, s$. What is the length of the bridge (in $m$)?

$A$ 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?

Walking at three-fourth of his usual speed, a man covers a certain distance in $2 \, \text{hours}$ more than the time he takes to cover the distance at his usual speed. The time taken by him to cover the distance with his usual speed is (in $\text{hours}$):

The ratio of the speed of a bus to that of a train is $15: 27$. Also,a car covered a distance of $720 \text{ km}$ in $9 \text{ hours}$. The speed of the bus is $\frac{3}{4}$ the speed of the car. How much distance will the train cover in $7 \text{ hours}$? (in $\text{km}$)

$A$ motor car completes a journey in $10 \, hours$. It covers the first half of the distance at $21 \, km/h$ and the remaining half at $24 \, km/h$. Find the total distance (in $km$).