1. The quick sell dealership started an ad campaign. During a 10 week campaign the dealer kept the following records:
# of adds per week (x)
6
20
0
14
25
16
28
18
10
8
# of cars sold per week (y)
15
31
10
T
28
20
40
25
12
15
(i) Given the covariance is 76.5 and the S(y) = 9.58, calculate the product moment correlation (r), correct to two decimal places.
(ii) Use your result to comment on the statement : The more ads posted, the more cars sold.
(iii) Given that the mean of y is 21.20, find the equation of the line of y on X.
Using the least squares regression line to predict the following:
(iv) Calculate the # of cards sold if 14 ads per week were published.
