the graph shows the distance in miles of a runner over x hours. what is the average rate of speed over the…

the graph shows the distance in miles of a runner over x hours. what is the average rate of speed over the interval 9, 11? running distance (in miles) 16 14 12 (11, 11) 10 8 f(x) 6 (9, 6) 4 2 (5, 1) (0, 0) 2 4 6 8 10 12 14 time (in hours)
Answer
Explanation:
Step1: Recall average - rate - of - change formula
The average rate of speed (average rate of change of distance with respect to time) over the interval $[a,b]$ is given by $\frac{f(b)-f(a)}{b - a}$, where $a = 9$, $b = 11$, $f(9)=6$ and $f(11)=11$.
Step2: Substitute values into formula
$\frac{f(11)-f(9)}{11 - 9}=\frac{11 - 6}{11 - 9}$.
Step3: Calculate the result
$\frac{11 - 6}{11 - 9}=\frac{5}{2}=2.5$ miles per hour.
Answer:
$2.5$ miles per hour