Answer: 62.5 km/hour is the average velocity of the train.
Step-by-step explanation:
Displacement of the train = 100 km + 150 km = 250 km
Total time train took =1 hour 15 min+ 45 min + 2 hours = 240 min = 4 hours
Average velocity=

62.5 km/hour is the average velocity of the train.