![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31ea979a9e91e2f1d1ffd2f3c6ccebf0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c452415b2ade7fc8a74e7624654839b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6efa7b9891f0371f6f0392fb086e705.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8eb4ccbf8f3e7c2ed20de44714256534.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0df5b38e19eb704481e963690276adf.png)
(Ⅰ)台风后居委会号召小区居民为台风重灾区捐款,小张调查的100户居民捐款情况如右下表格,在图2表格空白处填写正确数字,并说明是否有以上的把握认为捐款数额多于或少于500元和自身经济损失是否到4000元有关?
(Ⅱ)将上述调查所得到的频率视为概率. 现在从该地区大量受灾居民中,采用随机抽样方法每次抽取1户居民,抽取3次,记被抽取的3户居民中自身经济损失超过4000元的人数为. 若每次抽取的结果是相互独立的,求
的分布列,期望
和方差
.
附:临界值表
0.10 | 0.05 | 0.025 | |
![]() | 2.706 | 3.841 | 5.024 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/275753b45e1571d5777fcf649f4f05b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
![](https://img.xkw.com/dksih/QBM/2017/3/21/1648610927230976/1649157818138624/STEM/a0eea017a5f04c7fade7fee94058c3ee.png?resizew=363)
(1)现从乙班数学成绩不低于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1f959e5f8d89390f0f136f6acc9f6fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a17161b28b6ad8f57abc5b11e1b6c671.png)
(2)学校规定:成绩不低于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86608326541db75771f5de9db6187e6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b72fcdc709e77910cd36a26369648b3.png)
![](https://img.xkw.com/dksih/QBM/2017/3/21/1648610927230976/1649157818138624/STEM/cc541b25fa054a2ea37e5335fdc77001.png?resizew=393)
附:参考公式及数据
![](https://img.xkw.com/dksih/QBM/2017/3/21/1648610927230976/1649157818138624/STEM/5190b7b52aa04c2fbbc2a5569a411227.png?resizew=524)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4abb59695562b3a1295a251dc97da700.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b3779b4ea5477aebfe85113b0de1d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4abb59695562b3a1295a251dc97da700.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4abb59695562b3a1295a251dc97da700.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d07ae0b4264da6a8812454ffd2f20d94.png)
(1)在下图表格空白处填写正确数字,并说明是否有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0570f9b231be12b1f5476b10bbcac3c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4abb59695562b3a1295a251dc97da700.png)
(2)将上述调查所得到的频率视为概率. 现在从该地区大量居民中,采用随机抽样方法每次抽取
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4abb59695562b3a1295a251dc97da700.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ef5ccb0e7b118785332d753891a2679.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fc79c66ebaacd709ec9965b90a22b14.png)
每月平均经济收入达到![]() | 每月平均经济收入没有达到![]() | 合计 | |
捐款超过![]() | |||
捐款不超过![]() | |||
合计 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5f7bdc7bd13ba31d41e0b1071883576.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/356b05e46b10ee51c3e43546d73ec96c.png)
参考数据 | 当![]() ![]() |
当![]() ![]() ![]() | |
当![]() ![]() ![]() | |
当![]() ![]() ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d87f1411e04e9acc27c327aae4bc11bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/485c55c9b18a54433f87b3816fc120bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b0a89e3c30f6e4d4c5db4378b05d987.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17509b84c8c5c37be4cc4e71b445b8fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1926eb08a21a8b6558fcfd4c52a4a23b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfd121f4aeca8a78a320fca1fd1c4d07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d19130ab26685fff62362378e6c5c3c6.png)
男生平均每天运动的时间分布情况:
平均每天运动的时间 | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
人数 | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
女生平均每天运动的时间分布情况:
平均每天运动的时间 | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
人数 | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
(1)请根据样本估算该校男生平均每天运动的时间(结果精确到
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a87796ee30e6c5d5e6b6285b32abe10c.png)
(2)若规定平均每天运动的时间不少于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
①根据样本估算该校“运动达人”的数量;
②请根据上述表格中的统计数据填写下面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9119ded3b78b3c0bd24e79cb72eeab0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03099476ad68d3ad530d75d662100f14.png)
运动达人 | 非运动达人 | 总计 | |
男生 | |||
女生 | |||
总计 |
参考公式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3ad3450bca44d6c4925ffbd8b49d74f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/356b05e46b10ee51c3e43546d73ec96c.png)
参考数据:
![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
![](https://img.xkw.com/dksih/QBM/2015/2/5/1571980863660032/1571980869713920/STEM/c90c7d53b97f46779eab80956790cee8.png?resizew=287)
(1)从乙班样本的20个个体中,从不低于86分的成绩中随机抽取2个,求抽出的两个均“成绩优秀”的概率;
(2)由以上统计数据填写下面2x2列联表,并判断是否有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1900955145de5c6dfefaf3376937202e.png)
甲班(A方式) | 乙班(B方式) | 总计 | |
成绩优秀 | |||
成绩不优秀 | |||
总计 |
附:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bc485c58dbd6e50bfb352030f4a1c42.png)
P(![]() | 0.25 | 0.15 | 0.10 | 0.05 | 0.025 |
k | 1.323 | 2.072 | 2.706 | 3.841 | 5.024 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9893376adbc582b98d1287f1d38a72c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f61526d17d59d9319fbebcb194da1910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abe2f70554fb7ffc670c0f9bedde6502.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73514ef25f41ff0189d65313034bf695.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5749e5138778591f1c99da74ab8a888.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b98df418a221be80cd082639c5262de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f702ab683d2cc6d3a7ce1125797f8e1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/12/fe1bb95f-763f-4842-bf88-106c13a9830a.png?resizew=301)
(1)试根据频率分布直方图估计小区平均每户居民的平均损失;
(同一组中的数据用该组区间的中点值作代表);
(2)小明向班级同学发出倡议,为该小区居民捐款,现从损失超过4000元的居民中随机
抽出2户进行捐款援助,求抽出的2户居民损失均超过8000元的概率;
(3)台风后区委会号召该小区居民为台风重灾区捐款,小明调查的50户居民捐款情况如下表,
在图2表格空白外填写正确数字,并说明是否有95%以上的把握认为捐款数额超过或
不超过500元和自身经济损失是否超过4000元有关?
经济损失不超过4000元 | 经济损失超过4000元 | 合计 | |
捐款超过500元 | 30 | ||
捐款不超过500元 | 6 | ||
合计 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bc485c58dbd6e50bfb352030f4a1c42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/356b05e46b10ee51c3e43546d73ec96c.png)
0.15 | 0.10 | 0.05 | 0.025 | 0.010 | 0.005 | 0.001 | |
2.072 | 2.706 | 3.841 | 5.024 | 6.635 | 7.879 | 10.828 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca3bb63bf6d5d7f2f4d8e7144a8e690.png)
![](https://img.xkw.com/dksih/QBM/2023/12/13/3388238096220160/3388316766486528/STEM/97f4b7df54b94e93a19f3d433d2cb9cf.png?resizew=341)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)若采用按比例分配的分层随机抽样的方法,从月用电量不低于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ca51c8ef860c19e5b2af2db43e0f0e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd95d99f18906db59c942d4d08eb76a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
投入促销费用x(万元) | 2 | 3 | 5 | 6 |
商场实际营销额y(万元) | 100 | 200 | 300 | 400 |
(2)求出x,y之间的线性回归方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/929ef3bed0a4bdd22f39e036506dc481.png)
(3)若该商场计划营销额不低于600万元,则至少要投入多少万元的促销费用?
参考公式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8af4a4b7b2554c4a2cb102b15dbe167d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f149458ffc83c8f613f84386f529f476.png)