Question 10Which of the following is not true for mutually exclusive events?A. Pr(A∪B)=Pr(A)+Pr(B)B. Pr(A∩B)=0C. Pr(A∪B)′=1−Pr(A∪B)D. Pr(A∩B)=Pr(A)×Pr(B)E. Pr(A∪B)=Pr(A)+Pr(B)−Pr(A∩B)
Q. Question 10Which of the following is not true for mutually exclusive events?A. Pr(A∪B)=Pr(A)+Pr(B)B. Pr(A∩B)=0C. Pr(A∪B)′=1−Pr(A∪B)D. Pr(A∩B)=Pr(A)×Pr(B)E. Pr(A∪B)=Pr(A)+Pr(B)−Pr(A∩B)
Question Prompt: Question prompt: Identify which statement is not true for mutually exclusive events.
Definition of Mutually Exclusive Events: Mutually exclusive events cannot happen at the same time, so Pr(A∩B) must be 0.
Calculation of Pr(A∪B): For mutually exclusive events, Pr(A∪B) is indeed Pr(A)+Pr(B) because they cannot occur together.
Complement of Pr(A∪B): The complement of Pr(A∪B) is 1−Pr(A∪B), so option C is a true statement.
Calculation of Pr(A ∩ B): For mutually exclusive events, Pr(A ∩ B) cannot be Pr(A) × Pr(B) because Pr(A ∩ B) is 0, not the product of their individual probabilities.
General Addition Rule: Option E is a general addition rule for any two events, not just for mutually exclusive events. For mutually exclusive events, Pr(A∩B) is 0, so Pr(A∪B)=Pr(A)+Pr(B)−0, which simplifies to Pr(A)+Pr(B).
More problems from Transformations of quadratic functions