Exhibit 9-7 A Random Sample of 16 Statistics Examinations from a Large

question 66

Multiple Choice

Exhibit 9-7
A random sample of 16 statistics examinations from a large population was taken. The average score in the sample was 78.6 with a variance of 64. We are interested in determining whether the average grade of the population is significantly more than 75. Assume the distribution of the population of grades is normal.
-Refer to Exhibit 9-7. At 95% confidence, it can be concluded that the average grade of the population

• A)is not significantly greater than 75
• B)is significantly greater than 75
• C)is not significantly greater than 78.6
• D)is significantly greater than 78.6

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Definitions:

Degrees of Freedom

The number of values in a calculation that are free to vary without violating any constraints.

Contingency Table

A tabular method to display the frequency distribution of variables along with their joint distribution.

Contingency Table

A type of table used in statistics to summarize the relationship between two categorical variables, showing the frequency of various combinations of outcomes.

Nominal Variables

Variables that represent categories with no intrinsic ordering or hierarchy, such as gender, nationality, or brand.