Answer Happy

An engineer wanted to determine how the weight of a car affects gas mileage. The following data represent the weights of various cars and their gas mileages. Complete parts (a) through (d). (a) Determine which variable is the explanatory variable and which is the response variable. The explanatory variable is the weight and the response variable is the miles per gallon. The explanatory variable is the miles per gallon and the response variable is the weight. (b) Draw a scatter diagram of the data. Choose the correct scatter plot. Weight Miles per a Car (pounds) Gallon A 3475 20 B 3985 18 с 2690 26 D 2580 27 E 3300 23 O A. OB. 30-4 4000 mpg . Weight (lbs B. Click the icon to view the critical values table. 6 15+ 2500 4000 Weight (lbs) 25001 15 mpg 30 - X critical values for the correlation coefficient OC. OD 4000 Critical Values for Correlation Coefficient A 30- 12 mpg 2500+ 15 30 15- 2500 4000 Weight (lbs) mpg (c) Compute the linear correlation coefficient between the weight of a car and its miles per gallon. re (Round to three decimal places as needed.) (d) Does a linear relation exist between the weight of a car and its miles per gallon in the city? n 3 0.997 4 0.950 5 0.878 6 0.811 7 0.754 8 0.707 9 0.666 100.632 110.602 120.576 13 0.553 140.532 150.514 160.497 170.482 180.468 190.456 20 0.444 21 0.433 22 0.423 230.413 240.404 25 0.396 260.388 270.381 28 0.374 29 0.367 300.361 O A. There appears to be a negative linear association because ris negative and less than the negative critical value. OB. There appears to be a negative linear association because r is positive and greater than the critical value. O C. There is little or no evidence of a linear association since the absolute value ofr is less than the critical value. OD. There appears to be a positive linear association because ris positive and greater than the critical value. Statcrun