A factory manufactures cars with a warranty of 5 years on the engine and transmission. An engineer believes that the engine or transmission wil malfunction in less than 5 years. He tests a sample of 40 cars and find the average time to be 4.8 years with a standard deviation of 0.5. (a) State the null and alternative hypotheses. (b) At a 2% significance level, is there enough evidence to support the idea that the warranty should be revised?

A factory manufactures cars with a warranty of 5 years on the engine and transmission. An engineer believes that the engine or transmission wil malfunction in less than 5 years. He tests a sample of 40 cars and find the average time to be 4.8 years with a standard deviation of 0.5. (a) State the null and alternative hypotheses. (b) At a 2% significance level, is there enough evidence to support the idea that the warranty should be revised?

College Algebra

1st Edition

ISBN:9781938168383

Author:Jay Abramson

Publisher:Jay Abramson

Chapter9: Sequences, Probability And Counting Theory

Section9.7: Probability

Problem 3SE: What is an experiment?

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What is an experiment?
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