题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010828-95009.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010828-74682.gif)
(1)求甲至多命中2个且乙至少命中2个的概率;
(2)若规定每投篮一次命中得3分,未命中得
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010828-93613.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-24202.gif)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-85397.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-52317.gif)
∴甲至多命中2个球且乙至少命中2个球的概率为
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-15712.gif)
(2)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-59382.gif)
P(
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-24202.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010830-67418.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-24202.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010830-58894.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-24202.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010830-54982.gif)
P(
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-24202.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010830-21224.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010829-24202.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010831-18063.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010836-81793.jpg)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010837-35193.gif)
解析
核心考点
试题【(12分) 甲、乙两位篮球运动员进行定点投蓝,每人各投4个球,甲投篮命中的概率为,乙投篮命中的概率为.(1)求甲至多命中2个且乙至少命中2个的概率;(2)若规定】;主要考察你对离散型随机变量均值与方差等知识点的理解。[详细]
举一反三
甲,乙,丙三个同学同时报名参加某重点高校2012年自主招生.高考前自主招生的程序为审核材料和文化测试,只有审核过关后才能参加文化测试,文化测试合格者即可获得自主招生入选资格.因为甲,乙,丙三人各有优势,甲,乙,丙三人审核过关的概率分别为0.5,0.6,0.4,审核过关后,甲,乙,丙三人文化测试合格的概率分别为0.6,0.5,0.75.
(1)求甲,乙,丙三人中只有一人通过审核的概率;
(2)设甲,乙,丙三人中获得自主招生入选资格的人数为
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010800-63060.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010800-63060.gif)
(1)从盒中依次抽取两次卡片,每次抽取一张,取出的卡片不放回,求两次取到的卡片的数字既不全是奇数,也不全是偶数的概率;
(2)若从盒子中有放回的抽取3次卡片,每次抽取一张,求恰有两次取到卡片的数字为偶数的概率;
(3)从盒子中依次抽取卡片,每次抽取一张,取出的卡片不放回,当放回记有奇数的卡片即停止抽取,否则继续抽取卡片,求抽取次数X的分布列和期望。
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010732-68199.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010732-31325.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010725-58421.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010725-11411.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010726-97133.gif)
(1)旅客甲8∶00到站,设他的候车时间为
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010726-90427.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010726-90427.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010726-90806.gif)
(2)旅客乙8∶20到站,设他的候车时间为
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010726-99354.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010726-99354.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010727-15461.gif)
![](http://img.shitiku.com.cn/uploads/allimg/20191030/20191030010716-45771.png)