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**CFA Practice Question**

Events A and B are mutually exclusive. P(A) = 0.45, P(B) = 0.27. The probability of neither A nor B occurring equals ______.

A. 0.72

B. 0.88

C. 0.28

**Explanation:**The probability of neither A nor B occurring equals one minus the probability of either A or B occurring i.e. P(neither A nor B) = 1 - P(A or B). Now, P(A or B) = P(A) + P(B) - P(A and B). Also, for mutually exclusive events, P(A and B) = 0 by definition. Therefore, P(A or B) = 0.45 + 0.27 = 0.72. Finally, P(neither A nor B) = 1 - P(A or B) = 1 - 0.72 = 0.28.

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**User Contributed Comments**
4

User |
Comment |
---|---|

AkuK |
missed that "mutually exclusive" ... |

sh21 |
good question |

mary11 |
I was finally happy I may have got one of these questions right - then I missed the mutually exclusive portion. |

mrpman |
damn mutual exclusives!!!!!!! |