Answer:
The Chance Model
I am not convinced that my friend's method actually works as she claims. Taking one exam to prove that her claim works is not significant enough. My friend needs to take more tests. If a sample of tests yields similar results on the average, I will then be convinced. Otherwise, what has just happened is simply a question of chance.
Explanation:
The statistical significance of one test is not large enough for any decision maker to reject or fail to reject my friend's hypothesis or claim. More sample tests need to be taken such that my friend will score 70% or more in the tests to make her claim convincing.