In: Statistics and Probability
1. Previously, 20% of potential customers from St. Thomasville buy a certain brand of soap--say Brand A. To increase sales, the company conducts an extensive advertising campaign. At the end of the campaign, a random sample of 300 potential customers is interviewed and 80 customers prefer Brand A. Conduct an appropriate test to determine if the true proportion of customers that prefer Brand A soap is higher than 20%. Use a = 0.03.
5. A political campaign manager wants to know if the sample results can be used to conclude that the unemployment rate for 18- to 34-years-olds is significantly higher than the unemployment rate for all adults. According to the Bureau of Labor Statistics, the unemployment rate for all adults was 7.9%. Develop a hypothesis test that can be used to see if the conclusion that the unemployment rate is higher for 18- to 34-year-olds can be supported. In a sample of size 400 18- to 34-years-olds, there were 50 that indicated that they were unemployed. Let a = 0.05.
***Create null & alternate hypothesis, create rejection region, calculate test value & make conclusion to reject or not reject***