Step 1
The average rate of change is the rate at which one value within a function changes in relation to another. The average rate of change is usually used to determine the slope of a graphed function.
The formula for the average rate of change is written as;
Step 2
Consider the question below.
First, we will identify the two points corresponding to the interval
[tex]\begin{gathered} 11=a \\ 15=b \\ 79=f(a) \\ 89=f(b) \\ \text{Average rate of change=}\frac{f(b)-f(a)}{b-a} \\ \text{Average rate of change}=\frac{89-79}{15-11}=\frac{10}{4}=\frac{5}{2} \end{gathered}[/tex]
