A physical fitness trainer would like an easy method for estimating the percent body fat of her male customers. She measured the waist size (in.) and the percent body fat of 20 men and displayed the data in the scatterplot below.

Body Fat % 40 35- 30- 25- 20 15- 10- 32 Can waist size predict percent body fat? 34 38 Waist (in) 40 42 44 a) Find the equation of the regression line by computing the slope and the y-intercept. The mean waist size is 37.05 inches with a standard deviation of 3.82 inches. The mean body fat is 19.75% with a standard deviation of 9.56% and the correlation coefficient is 0.887. Show the calculations. b) Interpret the slope of the regression line in this context. Include the appropriate units of measurement.