OE
Since you know that the probability of event A is 1/2 and the probability of event B is 1/3 but you are not given any information about the relationship between events A and B, you can compute only the minimum possible value and the maximum possible value of the probability of the event A ∪ B.
The probability of A ∪ B is least if B is a subset of A; in that case, the probability of A ∪ B is just the probability of A, or 1/2.
The probability of A ∪ B is greatest if A and B do not intersect at all; in that case, the probability of A ∪ B is the sum of the probabilities of A and B, or \(\frac{1}{2}+\frac{3}{4}=56.\) With no further information about A and B, the probability that A or B, or both, will occur could be any number from 1/2 to 5/6 . Of the answer choices given, only 1/2 and 3/4 are in this interval.
The correct answer consists of Choices B and C.