# Question: Random samples of sizes n1 25 and n2

Random samples of sizes n1 = 25 and n2 = 20 were selected from populations A and B, respectively. From the samples, the standard deviations were computed to be s1 = 5.2 and s2 = 6.8.

a. Do the data provide substantial evidence to indicate the populations have different standard deviations? Use α = .05.

b. Estimate the relative sizes of the standard deviations by constructing a 95% confidence interval for the ratio of the standard deviations σ1/σ2.

c. The data and populations must satisfy what conditions in order for your test and confidence interval to be valid?

a. Do the data provide substantial evidence to indicate the populations have different standard deviations? Use α = .05.

b. Estimate the relative sizes of the standard deviations by constructing a 95% confidence interval for the ratio of the standard deviations σ1/σ2.

c. The data and populations must satisfy what conditions in order for your test and confidence interval to be valid?

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