有三條問題。她答對每條問題的概率是2/3，得出以下結果的概率是：
1，答錯一題
2，打錯全部題
3，最小答對一題
概率問題 有三條問題。她答對每條問題的概率是2/3，
2007-11-26 1:22 am
回答 (3)
2007-11-26 1:28 am
✔ 最佳答案
1. P(答錯一題) = [2/3 X 2/3 X (1 – 2/3)] X 3
= 4/9
2. P(答錯全部)
= (1 – 2/3) X (1 – 2/3) X (1 – 2/3)
= 1/27
3. P(最少答錯一題)
= 1 – P(全部答對)
= 1 – (2/3 X 2/3 X 2/3)
= 1 – 8/27
= 19/27
2007-11-25 17:56:53 補充：
3. P(最少答對一題) = 1 – P(全部答錯) = 1 – 1/27 (b part)= 26/27
參考: Myself~~~
2007-11-26 1:37 am
第 3題, 樓上好似錯左
P(最少答對一題)
= 1- P(全部答錯)
=1- 1/3 x 1/3 x 1/3
=1- 1/27
=26/27 //
P(最少答對一題)
= 1- P(全部答錯)
=1- 1/3 x 1/3 x 1/3
=1- 1/27
=26/27 //
2007-11-26 1:30 am
1. (1/3*2/3*2/3)*3
2. 1/3*1/3*1/3
3. (1/3*1/3*2/3)*3+(1/3*2/3*2/3)*3+2/3*2/3*2/3
唔知岩唔岩架~
2. 1/3*1/3*1/3
3. (1/3*1/3*2/3)*3+(1/3*2/3*2/3)*3+2/3*2/3*2/3
唔知岩唔岩架~
收錄日期: 2021-04-13 14:34:22
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071125000051KK03417