A college instructor gave identical tests to two randomly sampled groups of students. One group of 35 students took the test on paper, and another group of 75 students took the test online. A summary of the results is below. TEST TYPE PAPER ONLINE Sample Size 35 75 Mean 72.85 70.18 Standard Deviation 8.23 12.45 Construct a 95% confidence interval for the difference in mean scores between paper and online tests. Calculator Command: [ Select ] where: x?1 = [ Select ] Sx1 = [ Select ] n1 = [ Select ] x?2 = [ Select ] Sx2 = [ Select ] n2 = [ Select ] C-Level = [ Select ] Pooled = [ Select ] The true difference in mean scores between paper and online tests is between [ Select ] and [ Select ] The instructor claims that the mean scores are the same for both the paper and the online versions of the test. Does the confidence interval contradict this claim? [ Select ] Explain: [ Select ]
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The formula for the standard error of the difference in means is: SE = sqrt((s1^2/n1) + (s2^2/n2)) SE = sqrt((8.23^2/35) + (12.45^2/75)) SE ≈ 2.07 Show more…
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