Q:

The following table shows the​ weights, in hundreds of​ pounds, for six selected cars. Also shown is the corresponding fuel​ efficiency, in miles per gallon​ (mpg), for the car in city driving. Use the data provided in the table to complete parts ​a) through​d).Weight​ (hundreds of​ pounds)283335323029Fuel efficiency​ (mpg)202219222321​a) Determine the correlation coefficient between the weight of a car and the fuel efficiency.The correlation coefficient between the weight of a car and the fuel efficiency isr=​(Type an integer or decimal rounded to three decimal places as​ needed.)

Accepted Solution

A:
Answer:Step-by-step explanation:Given is a table showing  the​ weights, in hundreds of​ pounds, for six selected cars. Also shown is the corresponding fuel​ efficiency, in miles per gallon​ (mpg), for the car in city driving. Weight Fuel eff. x^2 xy y^2 X Y     28 20 784 560 400 3 22 9 66 484 35 19 1225 665 361 32 22 1024 704 484 30 23 900 690 529 29 21 841 609 441      Mean 26.16666667 21.16666667 797.1666667 549 449.8333333      Variance   112.4722222  1.805555556 Covariance -553.8611111                r -0.341120235     Correlaton coefficient =cov (xy)/S_x S_yCovariance (x,y) = E(xy)-E(x)E(y)The correlation coefficient between the weight of a car and the fuel efficiency is -0.341