The following table shows the balance of federal direct student loans (in billions of dollars) for selected years from 2011 and projected to 2023.
(a) Find the linear regression equation for the federal direct student loan balance as a function of the years past 2010. Report the model with three significant digit coefficients.
(b) What does the reported model predict for this balance in 2025?
(c) Write a sentence that interprets the slope of your linear regression equation.
Years ________________________Amount ($ billion)
2011 .......................................... 702
2013 .......................................... 940
2015 .......................................... 1220
2017 .......................................... 1500
2019 .......................................... 1775
2021 .......................................... 2000
2023 .......................................... 2250