Two men are standing on opposite ends of a bridge of $1200 \, m$ long. If they walk towards each other at the rate of $5 \, m/min$ and $10 \, m/min$ respectively,in how much time will they meet each other? (in $minutes$)

$A$ train covers a distance in $50 \text{ minutes}$ if it runs at a speed of $48 \text{ km/h}$. The speed at which the train must run to reduce the time of journey to $40 \text{ minutes}$ will be (in $\text{km/h}$):

Train $A$ starts its journey from Patna to Hazipur while train $B$ starts from Hazipur to Patna. After crossing each other, they finish their journey in $81\, \text{hours}$ and $121\, \text{hours}$ respectively. What will be the speed of train $B$ if the speed of train $A$ is $44\, \text{km/h}$?

Two trains of equal length take $10\, seconds$ and $15\, seconds$ respectively to cross a telegraph post. If the length of each train is $120\, metres,$ in what time (in $seconds$) will they cross each other when travelling in opposite directions?

$A$ train crosses a pole in $10 \, s$ and a platform,which is $40 \%$ longer than the length of the train,in $24 \, s$. If the length of the platform is $140 \, m$,what is the speed of the train in $m/s$?

Two cars $P$ and $Q$ start at the same time from $A$ and $B$ which are $120 \, km$ apart. If the two cars travel in opposite directions,they meet after $1 \, hour$,and if they travel in the same direction (from $A$ towards $B$),then $P$ meets $Q$ after $6 \, hours$. What is the speed of car $P$ (in $km/hr$)?