更新1:
''OR'' NOT ''AND''
更新2:
Ans: 0.1670
Probability 14
2009-07-07 6:37 pm
A hand of six cards is dealt from a well-shuffled deck. What is the probability that it contains exactly 2 kings, exactly 2 queens or exactly 2 jacks?
回答 (1)
2009-07-08 4:55 pm
✔ 最佳答案
Let the events of having 2 Kings, 2 Queens and 2 Jacks be K, Q and J respectively.Then P(K∪Q∪J) = P(K) + P(Q) + P(J) - P(K∩Q) - P(K∩J) - (Q∩J) + P(K∩Q∩J)
= [3(4C2)(48C4) - 3(4C2)(4C2)(44C2) + (4C2)(4C2)(4C2)] / (52C6)
= 0.1670
Note that it means KKQQQx, KKQQQQ, KKJJJx, KKJJJJ are allowed.
收錄日期: 2021-04-23 23:17:59
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090707000051KK00562