Question

he follo 2. Do heavier cars really use more gasoline? Suppose that a car is chosen at random. Let x be the weight of the car (in pounds), and let y be the miles per gallon (mpg). The following information is based on data taken from Consumer Reports (vol. 62, no. 4). cystolic 3400 5200 21 14 - Weight of Car (in pounds) 2700 4400 3200 4700 2300 4000 y-Miles per Gallon 30 19 24 13 29 17 . Find t a. Construct a scatterplot for the data in your calculator. Does there seem to be a strong, weak, or no correlation among the data? ஓம் b. Calculate the equation of the line of best fit (regression line). Label it appropriately and round to 3 decimal places...very important in this problem! 53. Fir c. Calculate the correlation coefficient. Label it appropriately and round to 3 decimal places. d. Calculate the coefficient of determination. Label it appropriately and round to 3 decimal places. e. What percentage of the variation in the miles per gallon can be explained by the line of best fit? f. You have a car that weighs approximately 3800 lbs. What mpg should you expect to get? 8. Your brother wants to buy an old truck that weighs approximately 5800 lbs. What mpg should he expect to get? h. Using table A-6 in your notes and a = .05, is the value for the correlation coefficient significant? Show your work. 1. Using part (h), can we conclude that there is a linear correlation between the weights of cars and the miles per gallon of all vehicles?

Answer 1

a scatter plot 32 1 30 28 10 Tam 2000 2500 3000 3500 4000 4500 5000 5500 - there seems to be a strong Correlation among the data 7290000 900 19360000 361 10240000 576 22090000 169 2700 30 81000 4400 19 836000 3200 24 76800 4700 13 61200 9 300 66700 2000 17 68000 3400 71400 5200 72800 841 289 5290000 16000000 11560000 27040000 196

(18870000) - 29900 (581400 81118870000) - 299002 ý = atby - EY. E x² - EX. Exy 167(118870000) - 2 nex² - (Ex) = 43.326 b = n.EXY - EX.EY 81581400) - 29900 (167) nex?- Ex)2 861188 70000) – (29900) - - 0.006 Lone of best fit is, % = 43.326 - 0.006x) I Correlation coefficient (p = nexy-Ex. EY. (nex-(894 8y? (8 y)2] 8 (581400) - 29900 (167) - = -0.946 18 (118870000) - 29900271 8(3773)- 16723 Coefficient of determination (+2) = (-0.946) ² = (0,895
according to HomeworkLib rules I have solved first 4 sub parts of the question