Question

Alocal retailer daims that the mean waiting time is less than 5 minutes. A random sample of 20 waiting times has a mean of 3.5 minutes with a standard deviation of 21 minutes. Ata -0.01, test the retailer's claim. Assume the distribution is normally distributed The test statistic was calculated to be 3.194 and the critical value from the distribution table is 2.539. What decision and conclusion can you make? Reject the wil hypothesis, there is enough evidence to conclude that the mean wait time is less than 5 minutes. O Tail to reject the null hypothesis, there enough evidence to conclude that the mean wait time is less than 5 minutes Failto feject the null hypothesis, there is not enough evidence to conclude that the mean wait times less than 5 minutes Reject the will hypothesis, there is not enough evidence to conclude that the mean wat time is less than 5 minutes Question 8 4 pts A manufacturer claims that the mean lifetime of its lithium batteries is 1200 hours. A homeowner thinks the mean is different. He selects 25 of these batteries and finds the mean lifetime to be 1180 hours with a standard deviation of 80 hours. Test the manufacturer's claim Usea -0.05. The test statistic was calculated to be 1.25and the p-value is 0.2233. What decision and conclusion can you make? o fail to reject the nul hypothesis, there is not enough evidence to conclude that the mean is different than 1200 hours O Reject the null hypothesis, there is not enough evidence to conclude that the mean is different than 1200 hours Reject the null hypothesis there is enough evidence to conclude that the mean is different than 1200 hours O Fail to reject the null hypothesis there is enough evidence to conclude that the mean is different than 1200 hours. Question 9 4 pts Assume that you plan to use a lificance level of a-005 to test the claim that 1.2. Use the given samole sizes and numbers of successes to find the pooled estimate Round your answer to the nearest thousandth Pi-10 Pi=91 2018 0175 0:37

Answer 1

Ans 7 The correct ans is A

Reject the null hypothesis, there is enough evidence to conclude that the mean wait time is less than 5 mins

Ans 8: The correct ans is A

Fail to reject the null hypothesis, there is not enough evidence to conclude that the mean is different than 1200 hours

Ans : the correct ans is B

0.140