Suppose Consumer Reports would like to investigate the relationship between the battery life, in hours, and the screen size, in diagonal inches, of a laptop computer. The following table shows a random sample of eight laptops and the battery life, in hours, and corresponding screen size, in inches, of each. This data can also be found in the Excel file laptop battery.xlsx.

Battery Life Screen Size Battery Life Screen Size 3.6 15.6 3.1 14.5 4.5 17.3 3.4 13.3 4.2 14.5 4.8 11.6 4.5 11.6 3.9 13.6

a. Calculate the sample covariance.

b. Calculate the sample correlation coefficient.

c. Describe the relationship between x and y.

140 AppendixLO1