The data displayed by the bar graph can be described by the mathematical model
$$p=\frac{4 x}{5}+25$$
where \(x\) is the number of years after 1980 and \(p\) is the percentage of U.S.
college freshmen who had an average grade of \(A\) in high school. Use this
information to solve Exercises \(97-98\)
a. According to the formula, in \(2010,\) what percentage of U.S. college
freshmen had an average grade of A in high school? Does this underestimate or
overestimate the percent displayed by the bar graph? By how much?
b. If trends shown by the formula continue, project when \(57 \%\) of U.S.
college freshmen will have had an average grade of \(\mathrm{A}\) in high
school.