Use the Five Step Hypothesis Method (please show all work)
7. A recent national survey found that high school students watched an average (mean) of 6.8 DVDs per month. A random sample of 36 college students revealed that the mean number of DVDs watched last month was 6.2, with a standard deviation of 0.5. At the .05 significance level, can we conclude that college students watch fewer DVDs a month than high school students?
17. The Rocky Mountain district sales manager of Rath Publishing, Inc., a college textbook publishing company, claims that the sales representatives make an average of 40 sales calls per week on professors. Several reps say that this estimate is too low. To investigate, a random sample of 28 sales representatives reveals that the mean number of calls made last week was 42. The standard deviation of the sample is 2.1 calls. Using the .05 significance level, can we conclude that the mean number of calls per salesperson per week is more than 40?
18. The Tampa Bay (Florida) Area Chamber of Commerce wanted to know whether the mean weekly salary of nurses was larger than that of school teachers. To investigate, they collected the following information on the amounts earned last week by a sample of school teachers and nurses
School teachers ($) 845 826 827 875 784 809 802 820 829 830 842 832
Nurses ($) 841 890 821 771 850 859 825 829
Is it reasonable to conclude that the mean weekly salary of nurses is higher? Use the .01
significance level. What is the p-value?
This solution shows step-by-step calculations in hypothesis testing by presenting null and alternative hypothesis, calculating the test statistic and comparing it to the p-value, and finally making a decision to accept or reject the null hypothesis.