In each exercise,
- (a) identify the claim and state H0 and Ha.
- (b) find the critical value and identify the rejection region,
- (c) find the test statistic,
- (d) decide whether to reject or fail to reject the null hypothesis, and
- (e) interpret the decision in the context of the original claim.
In Exercises 1–3, use the data, which list the hourly wages (in dollars) for randomly selected respiratory therapy technicians from three states. Assume the wages are
Maine: 20.92, 25.37, 23.06, 15.64, 27.72, 24.90, 19.26, 23.46, 18.49, 21.76, 22.36
Oklahoma: 22.70, 19.95, 17.85, 16.76, 21.32, 18.96, 17.99, 28.35, 25.30, 21.93
Massachusetts: 25.43, 23.21, 30.81, 26.62, 31.42, 31.34, 34.58, 28.22, 27.25, 22.83, 27.45, 27.71
1. At a = 0.05, is there enough evidence to conclude that the variances of the hourly wages for respiratory therapy technicians in Maine and Massachusetts are the same?
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Elementary Statistics: Picturing the World (7th Edition)
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