In: Statistics and Probability
According to the University of Nevada Center for Logistics Management, 6% of all merchandise sold in the United States gets returned (BusinessWeek, January 15, 2007). A Houston department store sampled 80 items sold in January and found that 15 of the items were returned.
a) Construct a 90% confidence interval for the proportion of returns at the Houston store.
b) Is the proportion of returns at the Houston store significantly larger than the returns for the nation as a whole? Provide statistical support for your answer