A school principal was interested in whether students in the

A school principal was interested in whether students in the chess club scored above or below the mean grade point average (GPA) at her school. She figured the average GPA at the school to be 2.55 with a standard deviation of .5 and noted that the distribution was approximately normal. She then figured the average GPA for 15 students in the chess club. Their mean GPA was 2.76. Did this group represent a population different from students in general at this school? (Use the .05 significance level, 2-tail.)Figure the confidence limits for the 95% confidence interval.

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