The diameter of steel rods manufactured on two different machines is being investigated. Suppose that the diameter of a rod is normally distributed, despite which machine is used to make the rod. Independent samples of n1=15 rods (from the first machine) and n2=17 rods (from the second machine) are randomly selected. The sample mean and sample variance of the first sample (of 15 rods) are xbar1=8.73, s1^2=0.34, respectively. The sample mean and sample variance of the second sample (of 17 rods) are xbar2=8.68 and s2^2=0.39, respectively. Based on these two samples, one can be 95% confident that that ratio of the two population variances, sigma1^2/sigma2^2 (i.e., the population variance of diameter of steel rods manufactured on the first machine over that on the second machine), lies between [Put Answer Here] and [Put Answer Here] . Please keep three digits past the decimal point.
The diameter of steel rods manufactured on two different machines is being investigated. Suppose that the diameter of a rod is
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