15)Drugstore.com was the first e-commerce company to offer Internet drugstore retailing.Drugstore.com customers were provided the opportunity to buy health, beauty, personal care, wellness, and pharmaceutical replenishment products over the Internet. At the end of 10 months of operation, the company reported that 44% of orders were from repeat customers (Drugstore.com Annual Report, January 2, 2000). Assume that Drugstore.com will use a sample of customer orders each quarter to determine whether the proportion of orders from repeat customers changed from the initial p=.44.

a. Formulate the null and alternative hypotheses.

b. During the first quarter a sample of 500 orders showed 205 repeat customers. What is the p-value? Use =.05. What is your conclusion?

16) An article about driving practices in Strathcona County, Alberta, Canada, claimed that 48% of drivers did not stop at stop sign intersections on county roads (Edmonton Journal, July 19, 2000). Two months later, a follow-up study collected data in order to see whether this percentage had changed.

a. Formulate the hypotheses to determine whether the proportion of drivers who did not stop at stop sign intersections had changed.

b. Assume the study found 360 of 800 drivers did not stop at stop sign intersections. What is the sample proportion? What is the p- value?