Isabelle and Taylor work together on a group quiz that has 15 multiple-choice questions, each with four choices for the possible answer. Unfortunately, neither had time to study, so they decide to randomly guess at all answers. Isabelle guesses answers for the first 7 questions, and Taylor guesses for the other 8 questions.
a. For any single question on the quiz, what is p = chance of a correct guess?
b. Let X = number of correct guesses that Isabelle makes. What are the values of n and p for the binomial distribution that describes X?
c. Let Y = number of correct guesses that Taylor makes. What are the values of n and p for the binomial distribution that describes Y?
d. Consider X + Y = total correct guesses that Isabelle and Taylor make. What are the values of n and p for the binomial distribution that describes X + Y?