甲乙两运动员进行射击训练,已知他们击中目标的环数都稳定在7,8,9,10环,且每次射击成绩互不影响,射击环数的频率分布表如下,
甲运动员
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124139789019193/SYS201310251241397890191016_ST/images0.png)
乙运动员
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124139789019193/SYS201310251241397890191016_ST/images1.png)
若将频率视为概率,回答下列问题,
(1)求甲运动员击中10环的概率
(2)求甲运动员在3次射击中至少有一次击中9环以上(含9环)的概率
(3)若甲运动员射击2次,乙运动员射击1次,ξ表示这3次射击中击中9环以上(含9环)的次数,求ξ的分布列及Eξ.
考点分析:
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ξ | | 1 | 2 | 3 |
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