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Test of hypothesis for difference between variances

10.56) A sample of 25 concession stand purchases at the October 22 matinee of Bride of Chucky showed a mean purchase of $5.29 with a standard deviation of $3.02. For the October 26 evening showing of the same movie, for a sample of 25 purchases the mean was $5.12 with a standard deviation of $2.14. The means appear to be very close, but not the variances. At alpha (a) = .05, is there a difference in variances? Show all steps clearly, including an illustration of the decision rule.

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10.56) A sample of 25 concession stand purchases at the October 22 matinee of Bride of Chucky showed a mean purchase of $5.29 with a standard deviation of $3.02. For the October 26 evening showing of the same movie, for a sample of 25 purchases the mean was $5.12 with a standard deviation of $2.14. The means appear to be very close, but not the variances. At alpha (a) = .05, is there a difference in variances? Show all steps clearly, including an illustration of the decision rule.

Test of variances of two populations

Denote the population providing the larger sample variance as 1

Data from the samples
Sample 1: Oct 22 matinee
Standard deviation of sample 1= s1 = 3.02 ...

Solution Summary

Tests the hypothesis for difference between variances.

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