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:

$A$ train of $320 \, m$ crosses a platform in $24 \, s$ at a speed of $120 \, km/h$. $A$ man crosses the same platform in $4 \, min$. What is the speed of the man in $m/s$?

$A$ person travels from $P$ to $Q$ at a speed of $40 \, km/h$ and returns from $Q$ to $P$ by increasing his speed by $50\%$. What is his average speed for the entire journey? (in $km/h$)

$A$ train $100 \, m$ long takes $3 \frac{3}{5} \, s$ to cross a man walking at the rate of $6 \, km/h$ in a direction opposite to that of the train. Find the speed of the train in $km/h$.

How many seconds will a $500 \, m$ long train take to cross a man walking with a speed of $3 \, km/h$ in the direction of the moving train, if the speed of the train is $63 \, km/h$?

$A$ person has to travel from point $A$ to point $B$ in a certain time. Travelling at a speed of $5 \, km/h$,he reaches $48 \, min$ late,and while travelling at a speed of $8 \, km/h$,he reaches $15 \, min$ early. What is the distance from point $A$ to $B$ (in $km$)?