Find the equation of the regression line for the number of years out of school and annual contribution data used in Section 9.1.

a. Identify n, ∑­x, ∑­y, ∑­xy, and ∑­x² from Try It Yourself 4 in Section 9.1.

b. Calculate the slope m and the y-intercept b.

c. Write the equation of the regression line.

Number of years out of school, x                 Annual contribution (in 1000s of $), y

1 …………………………………………………………………………..   12.5

10 …………………………………………………………………………..  8.7

5 …………………………………………………………………………..   14.6

15 …………………………………………………………………………..  5.2

3 …………………………………………………………………………..    9.9

24 …………………………………………………………………………..  3.1

30 …………………………………………………………………………..  2.7