A Company Claims That You Can Expect Your Car to Get

question 84

Essay

A company claims that you can expect your car to get one mpg better gas mileage while using their gasoline additive. A magazine did a study to find out how much a car's gas mileage improved while using the gasoline additive. The study used 36 cars and recorded the average mpg with and without the additive for each car in the study. The cars with the additive averaged 1.20 mpg better than without and had a variance of 0.36 (mpg)².
A) Specify the competing hypotheses to determine if the gasoline additive improved gas mileage by at least one mpg. Use the matched-pairs sampling.
B) Calculate the value of the test statistic and the critical value.
C) Make a conclusion at the 5% significance level.

• A) Specify the competing hypotheses to determine if the gasoline additive improved gas mileage by at least one mpg. Use the matched-pairs sampling.
• B) Calculate the value of the test statistic and the critical value.
• C) Make a conclusion at the 5% significance level.

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Definitions:

Twin-Study Method

A procedure for examining the role of genetics on personality in which pairs of monozygotic and dizygotic twins are compared.

Genetics

The study of heredity and the variation of inherited characteristics among living organisms.

Personality

Consistent behavior patterns and intrapersonal processes originating within the individual.

Monozygotic Twins

Twins that originate from a single fertilized egg, which then splits and develops into two genetically identical individuals.