## Functions Modeling Change: A Preparation for Calculus, 5th Edition

$24.5.$
General formula for average rate of change from $a$ to $b$: $\frac{f(b)-f(a)}{b-a}.$ Hence here: $\frac{T_2-T_1}{t_2-t_1}=\frac{45-(-4)}{32-30}=\frac{49}{2}=24.5.$