# Chi-square test of goodness of fit: Grade distribution

A professor in the psychology department would like to determine whether there has been a significant change in grading practices over the years. It is known that the overall grade distribution for the department in 1985 had 14% A's, 26% B's, 31% C's, 19% D's and 10% F's. A sample of n=200 psychology students from last semester produced the following grade distribution:

A B c D F

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32 61 64 31 12

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Do the data indicate a significant change in the grade distribution? Test at the .05 level of significance.

https://brainmass.com/statistics/chi-squared-test/chi-square-test-goodness-fit-grade-distribution-325037

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Statistics

A professor in the psychology department would like to determine whether there has been a significant change in grading practices over the years. It is known that the overall grade distribution for the department in 1985 had 14% As,26% Bs,31% Cs,19% Ds and 10% Fs. A sample of n=200 psychology students from last semester produced the following grade distribution:

A B ...

#### Solution Summary

The solution provides step by step method for the calculation of chi square test of goodness of fit. Formula for the calculation and Interpretations of the results are also included.