$A$ train is moving at a speed of $120 \; km/hr$. If the length of the train is $120 \; m$,how long will it take to cross a railway platform $130 \; m$ long (in $sec$)?

$A$ $300 \;m$ long train crosses a platform in $39 \;seconds$,while it crosses a signal pole in $18 \;seconds$. What is the length of the platform? (In $m$)

$A$ train $360 \; m$ long is running at a speed of $45 \; km/hr$. In what time (in $sec$) will it pass a bridge $140 \; m$ long?

Two trains running in opposite directions cross a man standing on the platform in $27 \;seconds$ and $17 \;seconds$ respectively, and they cross each other in $23 \;seconds$. The ratio of their speeds is

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