State University uses thousands of fluorescent light bulbs each year. The brand of bulb it currently uses has a mean life of 1000 hours. A competitor claims that its bulbs, which cost the same as the brand the university currently uses, have a mean life of more than 1000 hours. The university has decided to purchase the new brand if, when tested, the evidence supports the manufacturer's claim at the .05 significance level. Suppose 64 bulbs were tested with the following results: x? = 1027.5 hours, s = 80 hours. Conduct the test using ? = .05. Show all your steps including: State the null and alternative hypothesis, calculate the test statistic, draw the probability distribution and specify the rejection region.
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The alternative hypothesis (H1) is that the mean life of the new brand of bulbs is more than 1000 hours. H0: μ = 1000 H1: μ > 1000 Show more…
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