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Descriptive Statistics, Student and Enrollment Distribution

Question 1 and 2 involve the random variable x with probability distribution given below.

x -2 4 5 6 7
P(x) 0.15 0.05 0.3 0.1 0.4

determine the expected value of x.

determine the standard deviation of x.

Below is a compilation of student distribution in our four statistics classes from the summer of 2009.

course stat 200 stat 225 stat 230 stat 250

percentage 45.8 12.0 32.8 9.4

The enrollment report for the summer of 2011 is given as follows

course stat 200 stat 225 stat 230 stat 250

frequency 249 71 133 47

At the 1% significant level, do the data provide sufficient evidence to conclude that 2011's enrollment distribution differs from the 2009 distribution?

Show all work: include the hypotheses, the computation of the test statistic, state the critical value, and state the conclusion of the test.

Solution Summary

The following posting helps calculation expected value, standard deviation, and helps determine student distribution and enrollment distribution. Calculations are given in Excel.