An advertising agency is considering two advertisements for a major client. One of the advertisements is in black and white, and the other is in color. A market research firm randomly selects 50 male and 50 female customers of the client to evaluate the two advertisements. The firm finds that 39 of the 50 males prefer the color advertisement, whereas 46 of the 50 females preferred the color advertisement.
a. Place a 95% confidence on the difference in the proportions of males and females that prefer the color advertisement.
b. Does the confidence interval indicate that there is a significant difference in the proportions? Use a = .05.
c. Are the conditions for using a large- sample test to answer the question in part (b) satisfied? If not, apply an exact procedure.
d. Based on your results from parts (a) and (b), should the advertisement firm use different advertisements for male and female customers?