Question

A student believes that the average grade on the final examination in statistics is at least 85. She plans on taking a sample to test her belief. The correct set of hypotheses is_____.

a. H0: μ ≤ 85 Ha: μ > 85.
b. H0: μ < 85 Ha: μ ≥ 85.
c. H0: μ > 85 Ha: μ ≤ 85.
d. H0: μ ≥ 85 Ha: μ < 85.

Answer 1

Lyrics d null hypothesis μ₀ ≥ 85

alternative hypothesis Hₐ < 85

Explanation:

A student believes means she thinks the average (μ₀ ) is always bigger or at least 85

In mathematics terms that is she believes μ₀ ≥ 85

Therefore the alternative hypothesis need to be μ₀ < 85

So the test hypothesis should be:

H₀ null hypothesis ⇒ μ₀ ≥ 85

Hₐ alternative hypothesis μ₀ < 85