A manufacturer receives an order for fluorescent light bulbs

A manufacturer receives an order for fluorescent light bulbs. The order requires that the bulbs have a mean life span of 850 hours. The manufacturer selects a random sample of 25 fluorescent light bulbs and finds that they have a mean life span of 845 hours with a standard deviation of 15 hours. Test to see if the manufacturer is making acceptable light bulbs. Use a 95% confidence level. Assume the data are normally distributed. The mean age of bus drivers in Chicago is 50.3 years. If a hypothesis test is performed should you interpret a decision that fails to reject the null hypothesis There is not sufficient evidence to reject the claim Mu = 50.3. There is sufficient evidence to reject the claim Mu = 50.3. There is sufficient evidence to support the claim Mu = 50.3. There is not sufficient evidence to support the claim Mu = 50.3. You wish to test the claim that Mu not equal 14 at a level of significance of a = 0.05 and are statistics n = 35, x bar = 13.1. Assume the population standard deviation is 2.7. Compute of the standardized test statistic. Round your answer to two decimal places.

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