The change of the frequency of people waking up with respect to the sound level, 9% per 8 decibels.
What is linear function?
Linear function is the function in which the highest power of the unknown variable is one. Linear functions used to model the real life problem in the mathematical expressions.
The linear function with dependent variable y and independent variable x can be written as,
[tex]y=mx +c[/tex]
Here, (m) is the slope of the function and (c) is the y intercept.
The slope can be found out as,
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
The sound level is plotted on x-axis and frequency of people walking up (%) is plotted on y-axis. The slope of the line given the rate of change of y values with respect to x value.
In the graph given, the frequency of people walking up is 10 at 55 decibels and 55 at 95 decibels. The point, we get for this line are (55, 10) and (95, 55). Therefore the slope or the change of rate is,
[tex]\dfrac{dy}{dx}=\dfrac{55-10}{95-55}\\\dfrac{dy}{dx}=\dfrac{45}{40}\\\dfrac{dy}{dx}=\dfrac{9}{8}[/tex]
Hence, the change of the frequency of people waking up with respect to the sound level, 9% per 8 decibels.
Learn more about the linear function here;
https://brainly.com/question/15602982