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A random sample of 10 measurements on the breaking strength of a certain type of material...

A random sample of 10 measurements on the breaking strength of a certain type of material has a variance 3.21 psi2 . Repeated measurements on a second machine with 9 measurements shows a variance 2.32 psi2 . Assuming that the measurements are normally distributed, what is the ratio between the two variances at the 95% confidence level?

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