A random sample of n = 12 is drawn from a population that is normally distributed, and sample variance is s² = 19.3. Use α = 0.025 in testing HO: ?² ≤ 9.4 versus H1: ?² > 9.4.

Solution: We need to test the following hypotheses:

We need to use a Chi-Square test. The Chi-Square statistics is defined as

The critical

Chi Square
value for this right tailed test, with 11 degrees of freedom is given by

Since, we reject the null hypothesis.