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

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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). Based on the data from these two independent random samples that we assume to arise from two normal populations, we would like to test the null hypothesis that the two population variances are the same versus the alternative hypothesis that the first population variance, sigma1^2, is lower than that of the second population, sigma2^2. What is the p-value of this lower-tailed test? Please keep three digits past the decimal point. 

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