question archive Use R to answer all questions
Use R to answer all questions
Subject:StatisticsPrice: Bought3
Use R to answer all questions.
1. Suppose the manufacturer claims that the mean lifetime of a light bulb is more than 10,000 hours. In a sample of 30 light bulbs, it was found that they only last 9,900 hours on average. Assume the population standard deviation is 120 hours. At 0.05 significance level, can we reject the claim by the manufacturer? (Use the critical—value approach)
2. Suppose the manufacturer claims that the mean lifetime of a light bulb is more than 10,000 hours. In a sample of 30 light bulbs, it was found that they only last 9,900 hours on average. Assume the sample standard deviation is 125 hours. At 0.01 significance level, can we reject the claim by the manufacturer? (Use the p—value approach)
