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In: Statistics and Probability

Two random samples of 40 students were drawn independently from two populations of students. Assume their...

Two random samples of 40 students were drawn independently from two populations of students. Assume their aptitude tests are normally distributed (total points = 100). The following statistics regarding their scores in an aptitude test were obtained: xbar1= 76, s1 = 8, xbar2 = 72, and s2 = 6.5.
Test at the 5% significance level to determine whether we can infer that the two population means differ. (Note: You cannot necessarily assume that the populations have the same variances).

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