you select two independent random samples from populations with means u1 and u2. suppose the sample mean for population 1 is 25 and σ1=3 and the sample mean for population is 20 and σ2=4. the 95% confidence interval for u1-u2 is (4.02,5.98). what common sample size, n, was used to obtain this interval?
you select two independent random samples from populations with means u1 and u2. suppose the sample...
Independent random samples selected from two normal populations produced the sample means and standard deviations shown to the right. a) Assuming equal variances, conduct the test Ho: (u1-u2)=0 against Ha: (u1-u2)=/=0 using a=0.05 b) Find and interpret the 95% confidence interval for (u1-u2) Sample1: n1=17, x1=5.9, s1=3.8 Sample2: n2=10, x1=7.3, s2=4.8
In order to compare the means of two populations, independent random samples of 385 observations are selected from each population, with the results found in the table to the right. Complete parts a through e. Sample 1 Sample 2 X1 = 5,337 X2 = 5,298 s1 = 157 s2 = 191 a. use a 95% confidence interval to estimate the difference between the population means (u1 - u2). Interpret the confidence interval. b. test the null hypothesis H0: (u1 - u2)...
In order to compare the means of two populations, independent random samples of 395 observations are selected from each population, with the results found in the table to the right. Complete parts a through e below. Sample 2 x2 = 5,250 2-210 Sample 1 X,5,279 1-140 a. Use a 95% confidence interval to estimate the difference between the population means (μ1-μ2) . Interpret the confidence The confidence interval is Round to one decimal place as needed.) Interpret the confidence interval....
Independent random samples were selected from two quantitative populations, with sample sizes, means, and variances given below. Population 1 2 Sample Size 39 44 Sample Mean 9.3 7.3 Sample Variance 8.5 14.82 Construct a 90% confidence interval for the difference in the population means. (Use μ1 − μ2. Round your answers to two decimal places.) __________ to ____________ Construct a 99% confidence interval for the difference in the population means. (Round your answers to two decimal places.) __________ to _____________
Independent random samples were selected from two quantitative populations, with sample sizes, means, and standard deviations given below. n = n2 = 90, x1 = 125.3, %2 = 123.8, s, = 5.7, s, = 6.9 Construct a 95% confidence interval for the difference in the population means ( M M ) (Round your answers to two decimal places.) Find a point estimate for the difference in the population means, Calculate the margin of error. (Round your answer to two decimal...
Consider the following results for two independent random samples taken from two populations. Sample 1 Sample 2 n 1 = 40 n 2 = 35 x 1 = 13.8 x 2 = 11.3 σ 1 = 2.5 σ 2 = 3 What is the point estimate of the difference between the two population means? (to 1 decimal) Provide a 90% confidence interval for the difference between the two population means (to 2 decimals). Use z-table. ( , ) Provide a...
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, n2=46, x¯1=57.8, x¯2=75.3, s1=5.2 s2=11 Find a 94.5% confidence interval for the difference μ1−μ2μ1−μ2 of the means, assuming equal population variances. Confidence Interval =
Independent random samples were selected from two quantitative populations, with sample sizes, means, and standard deviations given below. n1 = n2 = 60 x1 = 125.3 x2 = 123.4 s1 = 5.7 s2 = 6.1 a) Construct a 95% confidence interval for the difference in the population means (μ1 − μ2). (Round your answers to two decimal places.) to b) Find a point estimate for the difference in the population means. c) Calculate the margin of error. (Round your answer...
Consider the following results for independent random samples taken from two populations. Sample 1 Sample 2 n1= 20 n2 = 40 x1= 22.1 x2= 20.6 s1= 2.9 s2 = 4.3 a. What is the point estimate of the difference between the two population means (to 1 decimal)? b. What is the degrees of freedom for the t distribution (round down)? c. At 95% confidence, what is the margin of error (to 1 decimal)? d. What is the 95% confidence interval...
Consider the following results for independent random samples taken from two populations. Sample 1 Sample 2 n 1 20 n 2 40 x2 20.4 1= 22.5 S 2 4.6 s1 2.1 a. What is the point estimate of the difference between the two population means (to 1 decimal)? b. What is the degrees of freedom for the t distribution (round down your answer nearest whole number)? c. At 95% confidence, what the margin of error (to 1 decimal)? d. What...