Dear student,
The average speed of train=distance covered by train/time taken by train to cover the distance.
As this is the activity question, collect the data and form the table of distance covered against time taken. Now, calculate the average speed of trains.
Mark the data in bar graph representation. Take distance covered on X-axis and time taken on Y-axis. Now mark them on the graph sheet.
Hence, you can compare the the average speed of different trains.
Regards.