27. The following data were collected during a study of consumer buying pat- terns. LO6 Observation X Y Observation X Y 1 15 74 8 18 78 2 25 80 9 14 70 3 40 84 10 15 72 4 32 81 11 22 85 5 51 96 12 24 24 88 6 47 95 7 30 83 a. Plot the data as a scatter plot. b. Obtain a linear regression line for the data. (You may use Excel's "-slope (RangeY,RangeX)" and "=intercept(RangeY,RangeX, where RangeY is the range of Excel cells containing the y values and RangeX is the range of Excel cells containing the x values)" to obtain the regression coefficients b and a, respectively. Alternatively, use Trendline in the Lay- out menu.) c. What percentage of the variation is explained by the regression line? (You may use Excel's "=RSQ(RangeY,RangeX)" to obtain r.) d. Use the equation determined in part b to predict the value of y for x = 41.