Math 102 OL Summer 2022- Section OLC 06/24/22 7:39 PM This quiz: 5 point(s) Question 1 of 4 possible Quiz: QUIZ 10 CHP 4 This question: 1 point(s) Submit quiz possible Use the value of the linear correlation coefficient to calculate the coefficient of determination. What does this tell you about the explained variation of the data about the regression line? About the unexplained variation? r= -0.243 Calculate the coefficient of determination. (Round to three decimal places as needed.) What does this tell you about the explained variation of the data about the regression line? % of the variation can be explained by the regression line (Round to one decimal place as needed.) About the unexplained variation? % of the variation is unexplained and is due to other factors or to sampling error. (Round to one decimal place as needed.) Time Remaining: 00:29:30 NexQuiz: QUIZ 10 CHP 4 Question 2 of 4 This question: 2 point(s) possible Submit quiz Suppose a doctor measures the height, x, and head circumference, y, of 8 children and obtains the data below. The correlation coefficient is 0.820 and the least squares regression line is y = 0. 169x + 12.818. Complete parts (a) and (b) below. Height, x 27.25 25.75 26.75 25.25 27.75 26.75 25.75 27.00 Head Circumference, y 17.4 17.2 17.1 17.1 17.6 17.4 17.2 17.4 (a) Compute the coefficient of determination, R2. R2 = % (Round to one decimal place as needed.) (b) Interpret the coefficient of determination and comment on the adequacy of the linear model. A. R2 of the variation in head circumference is not explained by the O B. R2 of the variation in head circumference is explained by the least-squares least-squares regression equation. The linear model appears to be regression equation. The linear model appears to be not appropriate. appropriate. C. R2 of the variation in head circumference is explained by the least-squares O D. R2 of the variation in head circumference is not explained by the regression equation. The linear model appears to be appropriate. least-squares regression equation. The linear model appears to be not appropriate. Time Remaining: 00:29:11 NexThis quiz: 5 point(s) Quiz: QUIZ 10 CHP 4 Question 3 of 4 possible This question: 1 point(s) possible Submit quiz Data were collected on monthly sales revenues (in $1000's) and monthly advertising expenditures ($100's) for a sample of drug stores. The regression line relating revenues (Y) to advertising expenditure (X) is estimated to be y = - 48.3 + 9.00x. What is the predicted sales revenue for a month in which $1,000 was spent on advertising? O A. $50,000 O B. $8,951.70 O C. $90,000 OD. $41,700 Time Remaining: 00:28:42 NMath 102 OL Summer 202 This quiz: 5 point(s) Quiz: QUIZ 10 CHP 4 Question 4 of 4 possible This question: 1 point(s) possible Submit quiz The data below are the final exam scores of 10 randomly selected statistics students and the number of hours they studied for the exam. What is the best predicted value for y given x = 7? Assume that the variables x and y have a significant correlation. Round the answer to the nearest whole number. Hours , x 3 5 2 8 2 4 4 5 6 3 Scores, y 65 80 60 88 66 78 85 90 90 71 O A. 90 O B. 91 O C. 92 OD. 89 Time Remaining: 00:28:25 Submit