Question

The function f(x)=12,500(0.87)^x models the value of a car x years after it is purchased

Answer 1

($12,500(.87^15) - $12,500(.87^11))/4 = -$288.47/year

($12,500(.87^5) - $12,500(.87))/4 = -$1,161.18/year

$288.47/$1,161.18 = about 1/4

The average rate of change between years 11 and 15 is about 1/4 of the average rate of change between years 1 and 5.