A tire manufacturer claims that its tires have a mean life of at least 50000 kms. A random sample of 36 of these tires is tested and the sample mean is 33000 kms. Assume the population's standard deviation is 3000 kms and the lives of tires are approximately normally distributed. To test the manufacturer's claim using the 5% level of significance the analyst should TS = (50000 - 33000) / 3000 TS = (33000 - 50000) / 3000 TS = (50000 - 33000) / (3000 / ?36) TS = (33000 - 50000) / (3000 / ?36)
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In this case, the null hypothesis (H0) is that the mean life of the tires is at least 50,000 kms, i.e., Ī¼ ā„ 50,000. The alternative hypothesis (H1) is that the mean life of the tires is less than 50,000 kms, i.e., Ī¼ < 50,000. Show moreā¦
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