Understanding Basic Statistics 6th Edition by Charles Henry Brase,Corrinne Pellillo Brase

Exercise 95

Critical Thinking For a class actively, your group has been assigned the task of generating a quiz question that requires use of the formula for conditional probability to compute P ( B | A ). Your group comes up with the following question: "If P ( A and B ) = 0.40 and P ( A ) = 0.20, what is the value of P ( B | A )" What is wrong with this question Hint: Consider the answer you get when using the correct formula, P ( B | A ) = P ( A and B )/ P ( A ).