Answer:
150 km/h
Step-by-step explanation:
A speed measures a distance traveled over a period of time. We usually express speed in terms of km/h for example.
That train travels 600 km in 4 hours.
To find its average speed, we just need to divide 600 km / 4 hours
We then get 150 km/h
That's said to be the average speed since it's the total distance in the total of time.... it might have been slower or faster at different points during that distance/time.