Answer:
Explanation:
Given that a professor sets a standard examination at the end of each semester for all sections of a course. The variance of the scores on this test is typically very close to 300.

(Two tailed test for variance )
Sample variance =480
We can use chi square test for testing of hypothesis
Test statistic =

p value = 0.0100
Since p <0.05 our significance level, we reject H0.
The sample variance cannot be claimed as equal to 300.