Fashion Line

1. A number of restaurants feature a device that allows credit card users to swipe their cards at the table. It allows the user to specify a percentage or a dollar amount to leave a tip. In an experiment to see how it works, a random sample of credit card users was drawn. Some paid the usual way, and some used the new device. The percent left as a tip was recorded and listed below. Population standard deviation for the usual pay is 1.33 and population standard deviation for the credit card( device) is 2.32 Can we infer that users of the device leave larger tips? Use a 2% significance level.

a) State the null and alternative hypothesesb) Calculate the test statistic by the formula and find the critical value from the table.c) Create the excel output and compare the test statistic and test critical with part (b)– (they have to be equal)d) Sketch the curve and highlight the rejection region(s).e) Make a statement about the claim.2. The effectiveness of an advertisement on TV designed to enhance the image of a brand name fashion line was tested on eight subjects. Their scores on a test were recorded before and after the advertisement. Assume the samples were taken from a normally distributed population. Test at the 1% level of significance. ( Hint : Use Matched Pairs formula)

a) State the null and alternative hypothesesb) Calculate the test statistic by the formula and find the critical value from the table.c) Create the excel output and compare the test statistic and test critical with part (b)– (they have to be equal)d) Sketch the curve and highlight the rejection region(s).e) Make a statement about the claim