1 . 为了更好满足人民群众的健身和健康需求,国务院印发了《全民健身计划(
)》.某中学为了解学生对上述相关知识的了解程度,先对所有学生进行了问卷测评,所得分数的分组区间为
、
、
、
、
,由此得到总体的频率分布直方图,再利用分层抽样的方式随机抽取
名学生进行进一步调研,已知频率分布直方图中
、
、
成公比为
的等比数列.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/6bf02bc6-92f9-434c-9379-1e39ad2251c7.png?resizew=209)
(1)若从得分在
分以上的样本中随机选取
人,用
表示得分高于
分的人数,求
的分布列及期望;
(2)若学校打算从这
名学生中依次抽取
名学生进行调查分析,求在第一次抽出
名学生分数在区间
内的条件下,后两次抽出的
名学生分数在同一分组区间
的概率.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e8a29886f0a21624a58f4589d70d9cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54c1aad87fae49406c84da4228a54ff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5593f690c46b319dba0a48d91ca5299a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7735f3df5bc6e44b3a769695d56e4a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8299ba56643f212cfdcc072fbc1c7763.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/337ad70b359ec3ab21b83fc34806f324.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/6bf02bc6-92f9-434c-9379-1e39ad2251c7.png?resizew=209)
(1)若从得分在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1f959e5f8d89390f0f136f6acc9f6fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a17161b28b6ad8f57abc5b11e1b6c671.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(2)若学校打算从这
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7735f3df5bc6e44b3a769695d56e4a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8299ba56643f212cfdcc072fbc1c7763.png)
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