4 hours after a goods train passed a station, another train travelling at a speed of 65km/hr following that goods train passed through that station. If after passing the station the train overtakes the goods train in 9 hours, what is the speed of the goods train?

Let the speed of the goods train be vkm/hr.
The goods train passes the station 4 hours before the second train. It then travels for another 9 hours before it is overtaken.
Therefore, the total time traveled by the goods train is:

Total time=4+9=13hours
The total distance traveled by the goods train in 13 hours is:

Distance=Speed×Time=v×13=13v
The second train travels at a speed of 65km/hr and takes 9 hours to overtake the goods train after passing the station.
The total distance traveled by the second train is:

Distance=65×9=585km
Since both trains cover the exact same distance from the station up to the point of overtaking:

13v=585
v=
13
585
​

v=45km/hr
Thus, the speed of the goods train is 45km/hr.