A tire manufacturer has been producing tires with an average life expectancy of 26,000 miles. Now the company is advertising that its new tires' life expectancy has increased. In order to test the legitimacy of the advertising campaign, an independent testing agency tested a sample of 6 of their tires and has provided the following data. Is the tire company using legitimate advertising? Calculate the appropriate test statistic to 3 decimals. The level of significance is 5%.

Life Expectancy

(In Thousands of Miles)

28

27

25

28

29

25