Homework SourseThe Rocky Mountain district sales manager of Rath Publishing
The Rocky Mountain district sales manager of Rath Publishing Inc., a college textbook publishing company, claims that the sales representatives make an average of 45 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 48. The standard deviation of the sample is 2.6 calls. Using the .05 significance level, can we conclude that the mean number of calls per salesperson per week is more than 45?
| The Rocky Mountain district sales manager of Rath Publishing Inc., a college textbook publishing company, claims that the sales representatives make an average of 45 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 48. The standard deviation of the sample is 2.6 calls. Using the .05 significance level, can we conclude that the mean number of calls per salesperson per week is more than 45? |
| H0 : ? ? 45 |
| H1 : ? > 45 |
Solution
test statistic is
Z=(xbar-mu)/(s/vn)
=(48-45)/(2.6/sqrt(28))
=6.11
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Reject H0. The mean number of calls is greater than 45 per week.
