Two trains $140 \; m$ and $160 \; m$ long run at a speed of $60 \; km/hr$ and $40 \; km/hr$ respectively in opposite directions on parallel tracks. The time (in $seconds$) which they take to cross each other is:

In what time (in $sec$) will a train $100 \; m$ long cross an electric pole,if its speed is $144 \; km/hr$?

Length of a train and that of a platform are equal. If with a speed of $135 \; km/hr$,the train crosses the platform in $40 \; seconds$,then the length (in $m$) of the train is:

Two trains are running in opposite directions with the same speed. If the length of each train is $120 \; m$,and they cross each other in $12 \; s$,then the speed of each train is (in $km/h$):

Two trains running at the rate of $45 \; km/h$ and $36 \; km/h$ respectively,on parallel tracks in opposite directions,are observed to pass each other in $8 \; seconds$. When they are running in the same direction at the same rate as before,a person sitting in the faster train observes that he passes the other in $30 \; seconds$. Find the length of the trains (in $m$).

$A$ train speeds past a pole in $15 \; \text{seconds}$ and a platform $100 \; \text{m}$ long in $25 \; \text{seconds}$. Its length is (in $\text{m}$):