A standardized test is given to a tenth grade class and a seventh grade class. The superintendent believes that the variance in performance for the two grades is different. The sample variance of a sample of 11 test scores from the tenth grade class is 29.33. The sample variance of a sample of 13 test scores from the seventh grade class is 9.85. Construct the 99% confidence interval for the ratio of the population variances. Round your answers to four decimal places.
Added by Diane S.
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33 / 9.85 F = 2.975 Show more…
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