Question 1-1

In 2016, the variance of scores in the class of OMG 321 was 21. Recently, a sample of 20 students had a variance of 25. We are interested in testing to see if there has been a significant change in the variance of scores in OMG 321. (=0.05?)

a) Formulate the hypotheses.

Question 1-2

Following Question 1-1, at a 95% confidence, calculate the test statistics (chi-square value) and test the hypotheses (round the first decimal). What are critical values? What is the conclusion?

Question 1-3

Following the information in Question 1-1, develop the 95% interval estimate of the variance for the population. Please round to the second decimal place.