Try making a simple drawing to help you visualize Fabio's route from home to each location and back home again.
10.2 miles
Let's illustrate the distance Fabio traveled on a number line.
We see that the distance between Fabio's home and the library is 2.3 + 0.7 + 2.1 = 5.1 miles. Since he took the same route back home, we can find the total distance he traveled by also adding the return trip.
2.3 + 0.7 + 2.1 + 5.1 = 10.2 miles
