Question 6.1 If X denotes the number of correct answers, what is P(X = 6)? What is P(6 X 20)? This number, equal to 0.196, is another example of a p-value. If we assume that a student is guessing, it is unlikely that they will get 6 or more correct, but not that unlikely. So if a student got 6 correct, we would not be able to reject the possibility that he knew nothing! This would reflect poorly on whatever teaching method the teacher was using. A random variable is just a variable X that takes a certain set of mutu- ally exclusive numerical values Sx for which there is a probability function P. In this case, Sx = {0, 1, 2, ..., 20} and P(X = x) = (20) (0.2) (0.8) (20-2),