We are given two points on the distance-time graph: (1, 40) and (3,130)
This means that:
At time 1 hour, the distance traveled was 40 km
At time 3 hours, the distance traveled was 130 km
We want to find the average speed during this 2 hour interval (from 1 hour to 3 hours).
Average speed is defined as:
Average Speed = Change in Distance / Change in Time
The change in distance is the distance traveled from 1 hour to 3 hours, which is 130 km - 40 km = 90 km
The change in time is 3 hours - 1 hour = 2 hours
So, the average speed is:
Average Speed = 90 km / 2 hours
= 45 km/hr
Therefore, the average speed during this interval of time is 45 km/hr.