$A$ train $125 \;m$ long passes a man,running at $5 \;km/hr$ in the same direction in which the train is going,in $10 \;seconds$. The speed of the train is (in $km/hr$):

$A$ 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?

$A$ train running at the speed of $60 \; km/hr$ crosses a pole in $9 \; seconds$. What is the length (in $m$) of the train?

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?

Two trains, one from Howrah to Patna and the other from Patna to Howrah, start simultaneously. After they meet, the trains reach their destinations after $9 \; \text{hours}$ and $16 \; \text{hours}$ respectively. The ratio of their speeds is

Two trains $250 \; m$ and $200 \; m$ long are running on parallel tracks at the rate of $36 \; km/hr$ and $45 \; km/hr$ respectively. In how much time (in $sec$) will they cross each other,if they are running in the same direction?