- CFA Exams
- CFA Level I Exam
- Study Session 2. Quantitative Methods (1)
- Reading 8. Probability Concepts
- Subject 4. Multiplication Rule for Independent Events
CFA Practice Question
Suppose that the probability of A is 0.80 and the probability of B is 0.60. If A and B are independent events, what is the probability of A or B?
A. 0.48
B. 0.80
C. 0.92
Explanation: Since A and B are independent events, P(A) = P(A|B) = 0.8 and P(AB) = P(A|B)P(B) = 0.80 x 0.60 = 0.48, so P(A or B) = P(A) + P(B) - P(AB) = 0.80+0.60-0.48=0.92.
User Contributed Comments 3
User | Comment |
---|---|
examcfa | P(A or B) = P(A)+ P(B) - P(A*B) , independent |
mc25456 | A and B are independent events, so P(A)=P(A|B)=0.8 and P(B)=P(B|A)=0.6 |
weiwei | Fot this one, P(A)=0.8 then P(A or B) > 0.8 |