Answer:
The average rate of change of the cost of a pack is 22 cents per year.
Another name for the average rate of change is slope.
Step-by-step explanation:
The average rate of change of the cost of a pack ([tex]r[/tex]), in monetary units per year, is equal to the change in the average cost of a pack ([tex]\Delta c[/tex]), in monetary units, divided by the change in time ([tex]\Delta t[/tex]), in years. Then, the average rate of change is:
[tex]r = \frac{\$\,5.31-\$\,0.88}{2000-1980}[/tex]
[tex]r = \$\,0.22\,\frac{1}{yr}[/tex]
The average rate of change of the cost of a pack is 22 cents per year.
Another name for the average rate of change is slope.