As a result of a random experiment, two independent events, X and Y may occur with the following probabilities:
Pr(X)=0.5 and Pr(Y)=0.8
Define the random variable U as the number of events X and Y which occur as a result of the random experiment. Thus, for example U=2 if both X and Y occur.
Find Pr(U=0), Pr(U=1) and Pr(U=2)
Discrete random variables probability question in description.?
2017-08-19 2:18 pm
回答 (1)
2017-08-19 2:31 pm
✔ 最佳答案
Pr(U = 0)= Pr([not X] and [not Y])
= Pr(not X) * Pr(not Y)
= (1 - 0.5) * (1 - 0.8)
= 0.1
Pr(U = 1)
= Pr({X and [not Y]} or {[not X] and Y}
= Pr(X) * Pr(not Y) + Pr(not X) * Pr(Y)
= 0.5 * (1 - 0.8) + (1 - 0.5) * 0.8
= 0.5
Pr(U = 2)
= Pr(X and Y)
= Pr(X) * Pr(Y)
= 0.5 * 0.8
= 0.4
OR:
Pr(U = 2)
= 1 - [Pr(U = 1) + Pr(U = 2)]
= 1 - (0.1 + 0.5)
= 0.4
收錄日期: 2021-04-24 00:39:47
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https://hk.answers.yahoo.com/question/index?qid=20170819061838AAqLBAC