Discussion:
Q: A Manufacturer claims that the mean lifetime of its Lithium batteries is 1400 hours. A homeowner select s 25 of these batteries and finds the mean lifetime to be 1380 hours with a standard deviation of 80 hours. Test the manufacturers claim. Use alpha = 0.05.
Round the test statistic to the nearest thousandth.
A) State your hypothesis: Ho: mean = 1400 and H1: mean <1400
B) Calculate your test statistic.
C) Use either the p-value or classical approach to determine whether to reject or not.
D) Use appropriate language to state your conclusion.