SOLUTION: A train moving at an average speed of 90 km/h takes 8 seconds to completely cross a bridge that is 80 meters long. Calculate the length of the train in meters

Let x be the length of the train, in meters.


The speed 90 km/h is   = 25 m/s.


In order for completely cross the bridge, the train should move the distance (80+x) meters.


From the other hand side, in 8 sdeconds the train covers the distance 25*8 = 200 meters.


Hence, 80+x = 200 meters,  which gives  x = 200-80 = 120 m  for the length of the train.


ANSWER.  The length of the train is 120 meters.