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A recent national survey reports that the general population gives the president an average rating of µ = 62 on a scale of 1 to 100. A researcher suspects that college students are likely to be more critical of the president than people in the general population. To test these suspicions, a random sample of college students is selected and asked to rate the president. The data for this sample are as follows: 44, 52, 24, 45, 39, 57, 20, 38, 78, 74, 61, 56, 49, 66, 53, 49, 47, 88, 38, 51, 65, 47, 35, 59, 23, 41, 50, 19.

For this problem, you are to calculate standard deviation in written form using the table on page 3. Once you are done with your calculations, enter the data above into the Excel program and cut and paste your output table onto page 4. Your written work for your standard deviation should match or come close to your Microsoft Excel output. Once you are done calculating descriptive statistics, perform a hypothesis test by typing in your responses on page 5 in this document.

a. Using the data listed above in problem 1, calculate by hand the standard deviation.
b. Using Microsoft Excel, type 'Ratings' in column A, cell 1. Below cell one, start typing your data in the A column.
c. Hypothesis Testing: Now that you have calculated your descriptive statistics to the data above, you will be able to use your results and perform a hypothesis test. In your results: state an appropriate null hypothesis, indicate the level of significance, identify the critical value, calculate the test statistic, evaluate the test statistic in light of the critical value, and make a decision about the null hypothesis.

A. Problem 1: President Ratings
Written work: Calculate standard deviation

Scores/Values Deviations Mean
(average)Deviation Variance
Squared Deviations Standard Deviation
N =
(X) (X - Mean)


Solution Summary

This solution is comprised of detailed step-by-step calculations and analysis of the given problem related to Statistics and provides students with a clear perspective of the underlying concepts. I have shown the calculations both by hand and in EXCEL for better understanding of the steps.