Question

Enrollment in a school has grown exponentially since the school opened. Below is a graph depicting this growth. Determine the average rate of change from x = 0 to x = 20.

An exponential graph has time in years on the x axis and enrollments on the y axis. An upward rising curve begins at zero comma thirty and passes through twenty comma eighty.

0.4

2.5

5

30

Answer 1

2.5

Explanation:

Answer 2

2.5

Explanation:

The average rate of the function f(x) from x=a to x=b is given by:

`(f(b)-f(a))/(b-a)`

From the question, the exponential function goes through (0,30) and (20,80).

This implies that f(0)=30 and f(20)=80

Therefore the average rate of change from x = 0 to x = 20 is

`=(f(20)-f(0))/(20-0)`

`=(80-30)/(20)`

`=(50)/(20)=2.5`

The second choice is correct