A retailer believes that its new advertising strategy will increase sales. Previously, the mean spending in 15 categories of consumer items in both the 18– 34 and 35+ age groups was $ 70.00.
a. Formulate a hypothesis test to determine if the mean spending in these categories has statistically increased.
b. After the new advertising campaign was launched, a marketing study found that the mean spending for 300 respondents in the 18– 34 age group was $ 75.86, with a standard deviation of $ 50.90. Is there sufficient evidence to conclude that the advertising strategy significantly increased sales in this age group?
c. For 700 respondents in the 35 + age group, the mean and standard deviation were $ 68.53 and $ 45.29, respectively. Is there sufficient evidence to conclude that the advertising strategy significantly increased sales in this age group?