Answer:
45.94 km/h
Step-by-step explanation:
Let the average speed be 48km/h for the first 86 km and 43 km/h for the remaining 54 km. We can calculate the time it takes to travel each of the segment:
For the first 86 km segment:

For the remaining 54 km segment:

So the total times it takes is

And the total distance she travels:

The average speed for the entire trip would be total distance divided by total time:
