# Using the 10 level of significance is there evidence

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Using the .10 level of significance, is there evidence that thepopulation mean is above \$300?A mean that is not in a confidence interval is rejected by theconfidence interval, and we say there is evidence.Question options:below the lower limit of the confidence intervalbelow the lower limit of the confidence intervaln the confidence interval
in the confidence intervalThe director of admissions at the University of Maryland,University College is concerned about the high cost of textbooksfor the students each semester. A sample of 25 studentsenrolled in the university indicates that x(bar) = \$315.40 and s= \$75. (Note the sample standard deviation is different from thefirst part).Using the .05 level of significance, is there evidence that thepopulation mean is above \$300?
Hide FeedbackFeedback: Find the interval width with =CONFIDENCE.T(0.05,75,25). Then add and subtract this from the mean, 315.40.The interval is 284.442 - 346.358The value of 300 is inside the interval, so we have no evidence that the actual population mean is over 300.6 / 6 pointsExplain the difference between parts A and C. In both parts weare asked whether or not there is evidence that the populationmean was over \$300.In part A: x(bar) = \$315.40; s = \$43.2; Sample size = 25In part C: x(bar) = \$315.40; s = \$75; Sample size = 25
The larger standard deviation adds uncertainty in the sample. The sample may have had some outliers.The smaller standard deviation adds uncertainty in the sample. The sample may have had some outliers.Hide FeedbackWe found evidence in part a but did not in part c. The reason is the large standard deviation in part c.86 / 100 - 86 %86 / 100 - 86 %Done
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