NO.PZ2022071202000041
问题如下：
Question
Event A: the fund will earn a return of 5%.
Event B: the fund will earn a return below 5%.
The least appropriate description of the events is that they are:
A portfolio manager estimates the probabilities of the following events for a mutual fund:选项：
A.dependent.
B.mutually exclusive.
C.exhaustive.
解释：
SolutionC is correct. Events are exhaustive when they cover all possible outcomes. Mutually exclusive means that only one event can occur at a time. Two events are dependent if the occurrence of one event does affect the probability of occurrence of the other event. In this situation, Event A and B are both mutually exclusive (because they cannot occur at the same time) and dependent (because if one event occurs, the probability of the other becomes zero). However, the two events are not exhaustive because they do not cover the event that the fund will earn a return above 5%.
A is incorrect. Events A and B are dependent because if one event occurs, the probability of the other becomes zero.
B is incorrect. Events A and B are mutually exclusive because they cannot occur at the same time.
老师请问A为什么不对？
