A car dealer investigated the association between the number of TV commercials ...

     A car   dealer investigated the association between the number of TV commercials he   ran each week and the number of cars he sold the following weekend. He found   the correlation to be r=0.56. During the time he collected the data he ran an   average of 12.4 commercials a week with a standard deviation of 1.8, and sold   an average of 30.5 cars with a standard deviation of 4.2. Next weekend he is   planning a sale, hoping to sell 40 cars. Create a linear model to estimate   the number of commercials he should run this week. Write a sentence   explaining your recommendation.