document.write( "Question 1081558: Within a university, students were randomly assigned to one of the two statistics instructors - instructor A and instructor B. After the assignment instructor a had 30 students and instructor B had 25 students. At the end of the semester, each class took the same standardized test. Instructor A students had an average test score of 78 with a standard deviation of 10; and Instructor B student had an average score of 85 with a standard deviation of 15. Test the hypothesis that instructor A and B are equally effective instructors. Use a 0.10 level of significance.
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Algebra.Com's Answer #695668 by stanbon(75887)\"\" \"About 
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Within a university, students were randomly assigned to one of the two statistics instructors - instructor A and instructor B. After the assignment instructor a had 30 students and instructor B had 25 students. At the end of the semester, each class took the same standardized test. Instructor A students had an average test score of 78 with a standard deviation of 10; and Instructor B student had an average score of 85 with a standard deviation of 15. Test the hypothesis that instructor A and B are equally effective instructors. Use a 0.10 level of significance.
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\n" ); document.write( "Ho: uA - uB = 0 (claim)
\n" ); document.write( "Ha: uA - uB # 0
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\n" ); document.write( "test statistic:: z(78-85) = (-7/sqrt[{10^2/30) + (15^2/25)] = -1.99
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\n" ); document.write( "P-value = 2*P(-100< z < -1.99) = 2*normalcdf(-100,-1.99) = 0.047
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\n" ); document.write( "Conclusion:: Since the P-value is less than 5%, reject Ho.
\n" ); document.write( "Conclusion:: The test results do not support the claim that
\n" ); document.write( "the instructors are equally capable at the 5% level of significance.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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