Answer:
The train travelled 300 km in all
Explanations:
Total time taken for the trip = 4 hours
For the first half of the trip (2 hours), it travels 60 km/h
For the second half of the trip (2 hours), it travels 100 km/h
For the first 2 hours:
In 1 hour, it travels 60 km
in 2 hours, it travels (2 x 60) = 120 km
For the second 2 hours:
In 1 hour, it travels 100 km
In 2 hours, it travels (2 x 100) = 200km
The distance traveled in the whole trip = Distance traveled in the first half of the journey + Distance traveled in the second half
The distance traveled in the whole trip = 120 km + 200 km
The distance travelled in the whole trip = 320 km