uestions Exercise 10.07 (Inferences About the Difference Between Two Population Means: Sigmas Known) 4 Question 6 of 10 Hint(s) Check My Work O Consumer Reports uses a survey of readers to obtain customer satisfaction ratings for the nation's largest supermarkets (Consumer Reports website). Each survey respondent is asked to rate a specified supermarket based on a variety O of factors such as quality of products, selection, value, checkout efficiency, service, and store layout. An overall satisfaction score summarizes the rating for each respondent with 100 meaning the respondent is completely satisfied in terms of all factors. Sample data representative of independent samples of Publix and Trader Joe's customers are shown below. O Excel File: data10-07.xisx Publix Trader Joe's my = 250 na = 300 F1 = 86 21 - 85 a. Formulate the null and alternative hypotheses to test whether there Is a difference between the population mean customer satisfaction scores for the two retailers. Ho : #1 - Pa equal to 0 H. All - Ma not equal to o b. Assume that experience with the Consumer Reports satisfaction rating scale indicates that a population standard deviation of 12 is a reasonable assumption for both retailers, Conduct the hypothesis test and report the p-value. p-value = (to 3 decimals) At a 0.05 level of significance what is your conclusion? I. Reject Ho. There is not sufficient evidence to conclude that the mean satisfaction scores differ for the two retailers. IT. Do not reject He . There is not sufficient evidence to conclude that the mean satisfaction scores differ for the two retailers. Ill. Reject Ho. There is sufficient evidence to conclude that the mean satisfaction scores differ for the two retailers. IV. Do not reject He. There is sufficient evidence to conclude that the mean satisfaction scores differ for the two retailers. II c. Which retailer, if either, appears to have the greater customer satisfaction? Trader Joe's Provide a 95% confidence interval for the difference between the population mean customer satisfaction scores for the two retailers. Enter negative values as negative numbers, if any. * to (to 2 decimals) 11:20