Probability
2010-07-03 6:06 am
Given that P(A) = 0.25, P(B) = 0.30 and P(C) = 0.45. Also, P(D|A) = 0.5, P(D|B) = 0.6 and P(D|C) = 0.4, find P(D|A'). [Note: P(A) + P(B) + P(C) = 1]
回答 (1)
2010-07-03 9:14 am
✔ 最佳答案
P(D|B) = 0.6P(D and B)/P(B) = 0.6
P(D and B)/0.3 = 0.6
P(D and B) = 0.18
P(D|C) = 0.4
P(D and C)/P(C) = 0.4
P(D and C)/0.45 = 0.4
P(D and C) = 0.18
P(A')
= P(B) + P(C)
= 0.3 + 0.45
= 0.75
P(D and A')
= P(D and (B or C))
= P(D and B) + P(D and C)
= 0.18 + 0.18
= 0.36
P(D|A')
= P(D and A')/P(A')
= 0.36/0.75
= 0.48
參考: andrew
收錄日期: 2021-04-13 17:21:22
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100702000051KK01649