The following results come from two independent random samples taken of two populations. Sample 1 Sample 2 n1 = 50 n2 = 25 x, = 13.6 x, = 11.6 o, = 2.3 o, = 3 (a) What is the point estimate of the difference between the two population means? (Use X1 - X2.) 2.0 (b) Provide a 90% confidence interval for the difference between the two population means. (Use x, - x,. Round your answers to two decimal places.) 0.88 to 3.12 (c) Provide a 95% confidence interval for the difference between the two population means. (Use x, - x,. Round your answers to two decimal places.) 0.67 to 3.33

Suppose you needed to test the claim that the two samples described below come from populations with the same mean. Assume that the samples are independent simple random samples. Sample 1: n1 = 13, a1 = 24, s1 = 7.55 Sample 2: n2 = 3, x2 = 21.9, s2 = 8.92 Find: (a) The estimated degree of freedom is (b) The standardized test statistic is (use Sample 1 - Sample 2)

A sample of n=41n=41 data values randomly selected from a normally distributed population has variance s2=30s2=30. Construct a 95% confidence interval for the population variance. Round your endpoints to one decimal place.

Given two independent random samples with the following results: n1=12x‾1=73s1=27n1=12x‾1=73s1=27   n2=12x‾2=102s2=22n2=12x‾2=102s2=22 Use this data to find the 95%95% confidence interval for the true difference between the population means. Assume that the population variances are equal and that the two populations are normally distributed.   Step 1 of 3 :   Find the point estimate that should be used in constructing the confidence interval.

7. What is the 95% confidence interval for the difference in the population means, µ1 - µ2, given the data from the two independent samples: n1 =56, x1= 58.2, s1= 4.3, n2=45, x2=60.2, s2=5.5 B. [-3.28 , -0.72] C. [-3.60, -0.40] D. [-3.65 , -0.35] A. [-3.96 , -0.04] 8. What is the 98% confidence interval for the difference in the population means, µ1 - µ2, given: n1= 22, x1= 41.4, s1= 5.9, n2= 19, x2= 43.2, s2= 6.5  D. [-3.48 , -0.12] B. [-3.07 , -0.53] A. [-3.12, -0.48] C. [-3.18, -0.42]

Two random samples are selected from two independent populations. A summary of the samples sizes, sample means, and sample standard deviations is given below:   n1=51, x¯1=59.2, s1=5.5 n2=50,x¯2=71.4,s2=10.4   Find a 93% confidence interval for the difference μ1−μ2μ1−μ2 of the means, assuming equal population variances. Confidence Interval =