Psychic Powers Bob is a self-proclaimed “mentalist” who claims that he can pass true false tests by guessing. In a test of Bob’s claim, he is given 14 true false questions, and Bob manages to correctly guess the answers to 2 of them. Is the number of correct answers unusual? Why or why not? Does Bob’s claim appear to be valid?

(Hint: When finding the required probability, refer to Table 4-1 and change “girl” to

“correct.” The probabilities of girls will be the same as the probabilities of correct guesses.)

4-2 Beyond the Basics