The graph shows Suhaila's position during a trip. Calculate Suhaila's average rate of travel between 2 pm and 2:30 pm.

Answer

From the picture, we can find the distance and time:

The "rate of travel" we've been talking about is an example of an **average rate of change**, abbreviated "average r.o.c.". When we talk about "rate of travel," we're talking about the average rate of change *of* distance traveled *with respect to* time. Similarly, if *x* is any independent variable (not necessarily time) and *y* is a dependent variable (not necessarily miles) related to *x*, we can find the average r.o.c. of *y* with respect to *x* on a given interval.