For Exercises 9 through 24, perform the following steps. Assume that all variables are
a. State the hypotheses and identify the claim.
b. Find the critical value.
c. Compute the test value.
d. Make the decision.
e. Summarize the results.
Use the traditional method of hypothesis testing unless otherwise specified.
20. School Teachers’ Salaries A researcher claims that the variation in the salaries of elementary school teachers is greater than the variation in the salaries of secondary school teachers. A random sample of the salaries of 30 elementary school teachers has a variance of $8324, and a random sample of the salaries of 30 secondary school teachers has a variance of $2862. At α = 0.05, can the researcher conclude that the variation in the elementary school teachers’ salaries is greater than the variation in the secondary school teachers’ salaries? Use the P-value method.
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