Question

Video rental stores are being replaced by streaming subscriptions. In one area, there

were 9 video rental locations in 1996, but by 2016, that number had dwindled to 4.
Assuming a constant decrease in the number of stores, calculate the unit rate of
change (slope) from 1996 to 2016.

Answer 1

The given problem is about the decrease of two variable, where
`x` represent years and
`y` represents video rental.

The ratio here refers to the slope of the linear decreasing behaviour, where pairs are (1996,9) and (2016, 4). The formula for the slope is

`m=(y_(2)-y_(1))/(x_(2)-x_(1) )=(4-9)/(2016-1996)=(-5)/(20)=-(1)/(4)\\ m=-0.25`

This means that the linear relation decreases, with a constant ratio of 0.25, that is, video rental decreases one per 4-years periods.