The table shown to the right gives the national average pupil-teacher ratio in public schools over selected years. Year Ratio a. Find the equation for the least squares line. Let x correspond to the number of years since 1992 and let y correspond to the average number of 1992 17.4 pupils per 1 teacher. 1994 17.7 b. Use the answer from part a to predict the pupil-teacher ratio in 2020. Does this seem realistic? 1996 16.9 c. Calculate and interpret the correlation coefficient. 1998 16.2 2000 15.8 . . . a. The equation for the least squares line is Y =. (Use integers or decimals for any numbers in the equation. Round to four decimal places as needed.)