22. PC World provided ratings for the top five small-office laser printers and five corporate laser printers (PC World, February 2003). The highest rated small-office laser printer was the Minolta-QMS PagePro 1250W, with an overall rating of 91. The highest rated corporate

a. Develop the estimated regression equation with speed as the independent variable.

b. Compute r2 . What percentage of the variation in price can be explained by the printing speed?

c. What is the sample correlation coefficient between speed and price? Does it reflect a strong or weak relationship between printing speed and cost?