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

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