共有9个基本事件,
玩家甲胜玩家乙的基本事件分别是:(石头,剪刀);(剪刀,布);(布,石头),共有3个.
所以,在1次游戏中玩家甲胜玩家乙的概率P=
3 |
9 |
1 |
3 |
(Ⅱ)X的可能取值分别为0,1,2,3.
P(X=0)=
C | 03 |
2 |
3 |
8 |
27 |
C | 13 |
1 |
3 |
2 |
3 |
12 |
27 |
C | 23 |
1 |
3 |
2 |
3 |
6 |
27 |
C | 33 |
1 |
3 |
1 |
27 |
X的分布列如下:
X | 0 | 1 | 2 | 3 | ||||||||
P |
|
|
|
|
8 |
27 |
12 |
27 |
6 |
27 |
1 |
27 |
3 |
9 |
1 |
3 |
C | 03 |
2 |
3 |
8 |
27 |
C | 13 |
1 |
3 |
2 |
3 |
12 |
27 |
C | 23 |
1 |
3 |
2 |
3 |
6 |
27 |
C | 33 |
1 |
3 |
1 |
27 |
X | 0 | 1 | 2 | 3 | ||||||||
P |
|
|
|
|
8 |
27 |
12 |
27 |
6 |
27 |
1 |
27 |