Suppose a study reports that the average price for a gallon of self-serve regular unleaded gasoline is $3.16. You believe that the ?gure is higher in your area of the country. You decide to test this claim for your part of the United States by randomly calling gasoline stations. Your random survey of 25 stations produces the following prices (all in $). Assume gasoline prices for a region are normally distributed. Do the data you obtained provide enough evidence to reject the claim? Use a 1% level of signi?cance.
3.27 3.29 3.16 3.20 3.37
3.20 3.23 3.19 3.20 3.24
3.16 3.07 3.27 3.09 3.35
3.15 3.23 3.14 3.05 3.35
3.21 3.14 3.14 3.07 3.10