Answer
Net change: 35
Average rate of change: $\frac{7}{4}$
Work Step by Step
We find the net change from $x=10$ to $x=30$:
$g(30)-g(10)=30--5=35$
Next we find the average rate of change for this interval:
$\frac{g(30)-g(10)}{30-10}=\frac{35}{20}=\frac{7}{4}$
