Question

Given the function defined in the table below, find the average rate of change, in simplest form, of the function over the interval 4, is less than or equal to, x, is less than or equal to, 204≤x≤20.
xx f, of, xf(x)
44 44
1212 66
2020 88
2828 1010

Answer 1

Average rate of change = (f(20) − f(4)) / (20 − 4).

From the table f(20) = 8 and f(4) = 4, so (8 − 4)/(20 − 4) = 4/16 = 1/4.