In throwing a biased coin , the probability of getting a headis 1/5. If the coin is thrown three times, find the probabiliyt of getting
(a) 2 heads and 1 tail
(b) 3 tails,
(c) at least 1 head
排列與組合(a Biased coin)?
2016-02-04 4:37 pm
回答 (1)
2016-02-04 5:14 pm
✔ 最佳答案
(a)P(2 heads and 1 tail)
= C(3,2) (1/5)² C(1,1) (1 - 1/5)
= 12/125
(b)
P(3 tails)
= (1 - 1/5)³
= 64/125
(c)
P(at least 1 head)
= 1 - P(3 tails)
= 1 - 64/125
= 61/125
收錄日期: 2021-04-23 23:46:58
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20160204083724AAR0wxw