7) A tire manufacturer has been producing tires with an average life expectancy of 26,000 miles. Now the company is advertising that their new tires' life expectancy has increased. In order to test the legitimacy of their advertising campaign, an independent testing agency tested a sample of 85 of their tires. The agency found the mean of the 85 tires to be 27,000 miles and the standard deviation to be 3,970 miles. Use a 0.01 level of significance and test to determine whether the company is using legitimate advertising. (Show all seven steps.)

7) A tire manufacturer has been producing tires with an average life expectancy of 26,000 miles. Now the company is advertising that their new tires' life expectancy has increased. In order to test the legitimacy of their advertising campaign, an independent testing agency tested a sample of 85 of their tires. The agency found the mean of the 85 tires to be 27,000 miles and the standard deviation to be 3,970 miles. Use a 0.01 level of significance and test to determine whether the company is using legitimate advertising. (Show all seven steps.)

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Description: 7) A tire manufacturer has been producing tires with an average life expectancy of 26,000 miles. Now thecompany is advertising that their new tires' life expectancy has increased. In order to test the legitimacy oftheir advertising campaign, an inde

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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The America Automobile Association reported that the mean price of a gallon of regular grade gasoline in the United States in October 2020 was $2.82. An economist is interested in determining whether the mean price of regular grade gasoline is cheaper (less than) in New York State. To test this, the economist sample 50 gas stations in NY and find the mean price of regular grade gasoline to be $2.77. Assume the standard deviation for the price of regular grade gasoline is $0.15. Use the critical value method to perform a hypothesis test at the 0.05 level of significance. a. Define the parameter we are testing and setup a hypothesis test to see if the mean price of gas is cheaper in NY compared to the national mean: b. Calculate the test statistics for this hypothesis test. c.What is the critical value for this hypothesis test?
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