Chapter 2.6, Problem 98E

The bar graph shows the population of the United States in millions for seven selected years.

Here are two function that model the data:

$\begin{array}{cc}M(x)=1.48x+115.1& \begin{array}{l}\text{Male}\text{U}\text{.S}\text{.pepolalias, }M(x),\text{is aillises,}\\ xyearafter1985\end{array}\\ F(x)=1.44x+120.9& \begin{array}{l}\text{Female}\text{U}\text{.S}\text{.pepolalias, }F(x),\text{is aillises,}\\ xyearafter1985\end{array}\end{array}$

Use the functions to solve Exercises 97-98.

a. Write a function that models the difference between the female U.S. population and the male U.S. population for the years shown in the bar graph.

b. Use the function from par (a) to find how many more women than men there were in the U.S. population in 2010.

c. Does the result in part (b) overestimate or underestimate the actual difference between the female and male population in 2010 shown by the bar graph? By how much?