[數學]機會率問題
2011-09-27 1:16 am
Suppose that a bag contains 10 coins: 4 are fair, 3 are biased with probability of heads 1/3,
and 3 have heads on both sides. A coin is chosen at random from the bag and is then tossed.
(1) Find the probability that a tail is observed;
(2) Given that a tail is observed, find the probability that the chosen coin was a fair one.
回答 (1)
2011-09-27 1:50 am
✔ 最佳答案
1)P(a tail is observed)= P(The chosen dice is fair and get tail) + P(The chosen dice is probability of heads 1/3 and get tail)= (4/10)(1/2) + (3/10)(1 - 1/3)= 2/52)P(Given that a tail is observed that the chosen coin was a fair one)= P(The chosen dice is fair and get tail) / P(a tail is observed) = (4/10)(1/2) / (2/5)= 1/2
收錄日期: 2021-04-21 22:21:30
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20110926000051KK00378