$A$ car traveling at a speed of $40 \, km/h$ can complete a journey in $9 \, hours$. How long will it take to travel the same distance at $60 \, km/h$? (in $hours$)

$A$ man travels $360 \, km$ in $4 \, hrs$,partly by air and partly by train. If he had travelled all the way by air,he would have saved $\frac{4}{5}$ of the time he was in train and would have arrived at his destination $2 \, hrs$ early. Find the distance he travelled by train (in $km$).

$A$ train running at the speed of $84 \, km/h$ passes a man walking in the opposite direction at the speed of $6 \, km/h$ in $4 \, s$. What is the length of the train (in $meters$)?

Two trains started at the same time,one from $A$ to $B$ and the other from $B$ to $A$. If they arrived at $B$ and $A$ respectively $4 \ hours$ and $9 \ hours$ after they passed each other,the ratio of the speeds of the two trains was:

Ramesh crosses a $600 \, m$ long street in $5 \, \text{minutes}$. His speed in $km/h$ is:

Two boys jointly begin to write a booklet containing $817$ lines. The first boy starts with the first line and writes $200$ lines an hour. The second boy starts with the last line,then writes line $816$ and so on,proceeding backwards at the rate of $150$ lines an hour. They will meet on: