5.1

You may need to use the appropriate appendix table or technology to answer this question. A report states that adults 18- to 24- years-old send and receive 128 texts every day. Suppose we take a sample of 25- to 34- year-olds to see if their mean number of daily texts differs from the mean for 18- to 24 year-olds. (a) State the null and alternative hypotheses we should use to test whether the population mean daily number of texts for 25 to 34-yearolds differs from the population daily mean number of texts for 18- to 24year-olds. (Enter != for a as needed.) H0: (b) Suppose a sample of thirty 25- to 34yearolds showed a sample mean of 118.7 texts per day. Assume a population standard deviation of 33.17 texts per day. Compute the pvalue. (Round your answer to four decimal places.) (c) With a = 0.05 as the level of signicance, what is your conclusion? 0 Reject H0. We can conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds. O Reject H0. We cannot conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24-year-olds. Q Do not reject H0. We can conclude that the population mean daily texts for 25- to 34year-olds differs signicantly from the population mean of 128 daily texts for 18- 24yearolds. 0 Do not reject H0. We cannot conclude that the population mean daily texts for 25 to 34year-olds differs signicantly from the population mean of 128 daily texts for 18 24-yearolds. (d) Repeat the preceding hypothesis test using the critical value approach. State the null and alternative hypotheses. (Enter != for ; as needed.) H0: Ha: Find the value of the test statistic. (Round your answer to two decimal places.) :1 State the critical values for the rejection rule. (Use a = 0.05. Round your answer to two decimal places. [f the test is one-tailed, enter NONE for the unused tail.) test statistic S :] test statistic 2 :] State your conclusion. O Reject H0. We can conclude that the population mean daily texts for 25- to 34-yearolds differs significantly from the population mean of 128 daily texts for 18- 24year-olds. O Reject H0. We cannot conclude that the population mean daily texts for 25- to 34-year-olds differs significantly from the population mean of 128 daily texts for 18- 24year-olds. 0 Do not reject H0. We can conclude that the population mean daily texE for 25- to 34year-olds differs signicantly from the population mean of 128 daily texts for 18- 24yearolds. 0 Do not reject H0. We cannot conclude that the population mean daily texts for 25- to 34year-olds differs signicantly from the population mean of 128 daily texts for 18 24-yearolds