$A$ person covers half of his journey at $30 \text{ km/h}$ and the remaining half at $20 \text{ km/h}$. The average speed for the whole journey is (in $\text{km/h}$)

$A$ speed of $45\, km/h$ is equivalent to which speed in $m/s$?

$A$ bus takes $15\, hours$ to travel from Delhi to Chandigarh. The bus travels for one-third of the total time at a speed of $80\, km/h$. It travels for $40\%$ of the remaining time at a speed of $70\, km/h$. It travels for $\frac{2}{3}$ of the remaining time at a speed of $85\, km/h$,and the rest of the time at a speed of $100\, km/h$. What is the total distance covered by the bus?

If the length of the train is $700 \, m$ and the length of the platform is $500 \, m$,find the time taken by the train moving at $54 \, km/h$ to cross the platform (in $sec$).

$A$ person started his journey in the morning. At $11:00 \, am$ he covered $\frac{3}{8}$ of the journey and on the same day at $4:30 \, pm$ he covered $\frac{5}{6}$ of the journey. He started his journey at ..... $am$

$A$ car covers a distance of $330 \, km$ in a certain amount of time at a speed of $55 \, km/h$. What is the average speed of a bike that covers a distance of $15 \, km$ less than the car in $1 \, hour$ less than the time taken by the car? (in $km/h$)