The sales manager gathered information on the numbers of sales calls made and the number of copiers sold for a random sample of sales representative. Is there a positive correlation between calls made and copiers? Test at the 0.05 level of significance. Determine the 90% prediction interval for 60 number of calls made. *
Calls,X Sold. Y
20 40
20 50
40 60
50 90
40 80
20 40
40 60
30 60