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10. Hypothesis Testing for Two Samples - Part 1 of 2!
10. Hypothesis Testing for Two Samples / Two Means - Known Variance / Problem 12
Problem 12

A researcher wants to test if the mean score of group A is greater than that of group B at the α=0.05 \(\alpha\) = 0.05 significance level. The populations are normal, independent, and have known standard deviations. Population statistics: σ1=25 \(\sigma\)_1 = 25 , σ2=20 \(\sigma\)_2 = 20 . Sample statistics: xˉ1=82 \(\bar{x}\)_1 = 82 , n1=64 n_1 = 64 ; xˉ2=78 \(\bar{x}\)_2 = 78 , n2=49 n_2 = 49 . What is the result of the hypothesis test?