Question

4.   The 8th-grade national norm for a social science test is a score of 120 with...

4.   The 8th-grade national norm for a social science test is a score of 120 with a
   standard deviation of 10. The research director of a school district wants to
   know how the scores of pupils in his district compare with this standard. He
   selects a sample of 80 students and finds a sample mean of 123 and a
   sample standard deviation of 9.50. Test the null hypothesis at the.05 level of
   significance and state your conclusions. Be sure to follow all steps of the
   hypothesis testing procedure.

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