![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f14db37344529d273e36d835241d0d39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ca98d80a6b806a27c46ae078dd6dabe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8c4c029e552954bd493b49aeab82d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
A:两球的颜色相同且号码相邻;B: 两球的颜色相同,但号码不相邻;
C: 两球的颜色不同,但号码相邻;D: 两球的号码相同;E: 其它情况.
经营者打算将以上五种类别中最不容易发生的一种类别对应一等奖,最容易发生的一种类别对应二等奖,其他类别对应三等奖.
(1)一、二等奖分别对应哪一种类别(用字母表示即可);
(2)若一、二、三等奖分别获得价值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d07ae0b4264da6a8812454ffd2f20d94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db6715812431e70da0cf0c97f0e0efe7.png)
3 . 某纺织厂为了生产一种高端布料,准备从A农场购进一批优质棉花,厂方技术员从A农场存储的优质棉花中随机抽取了100处棉花,分别测量了其纤维长度(单位:mm)的均值,收集到100个样本数据,并制成如下频数分布表:
长度(单位:mm) | [23,25) | [25,27) | [27,29) | [29,31) | [31,33) | [33,35) | [35,37) | [37,39] |
频数 | 4 | 9 | 16 | 24 | 18 | 14 | 10 | 5 |
(1)求这100个样本数据的平均数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c85481cd7e94130ef3aa05b4a39e79cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/671f43c79d612c93a6d160335e86e177.png)
(2)将收集到的数据绘成直方图可以认为这批棉花的纤维长度服从分布
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1290917c2c835b61384480b335cc1d13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/594f4ea0d5f4a741355161af9eb34104.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48d1316cf501a47b6d75594091d5f4a4.png)
①利用正态分布,求;
②纺织厂将A农场送来的这批优质棉进行二次检验,从中随机抽取20处测量其纤维均值yi(i=1,2…,20),数据如下:
y1 | y2 | y3 | y4 | y5 | y6 | y7 | y8 | y9 | y10 |
24.1 | 31.8 | 32.7 | 28.2 | 28.4 | 34.3 | 29.1 | 34.8 | 37.2 | 30.8 |
y11 | y12 | y13 | y14 | y15 | y16 | y17 | y18 | y19 | y20 |
30.6 | 25.2 | 32.9 | 27.1 | 35.9 | 28.9 | 33.9 | 29.5 | 35.0 | 29.9 |
若20个样本中纤维均值的频率不低于①中
即可判断该批优质棉花合格,否则认为农场运送时掺杂了次品,判断该批棉花不合格.按照此依据判断A农场送来的这批棉花是否为合格的优质棉花,并说明理由.
附:若,则
,
,
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/11/31e7b8d5-2772-417b-80fe-a6bc29149695.png?resizew=159)
(1)从甲、乙两车间分别随机抽取2个零件,求甲车间至少一个零件合格且乙车间至少一个零件合格的概率;
(2)质检部门从甲车间8个零件中随机抽取4件进行检测,若至少2件合格,检测即可通过,若至少3件合格,检测即为良好,求甲车间在这次检测通过的条件下,获得检测良好的概率;
(3)若从甲、乙两车间12个零件中随机抽取2个零件,用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
5 . 如图所示,在直四棱柱中,当底面四边形ABCD满足条件
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9c214cc074cf24aa90f2dfb01de102a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
长度(单位:mm) | [23,25) | [25,27) | [27,29) | [29,31) | [31,33) | [33,35) | [35,37) | [37,39) |
频数 | 4 | 9 | 16 | 24 | 18 | 14 | 10 | 5 |
(1)求这
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
(2)①用频率估计概率,求从这批棉花中随机抽取处期限为平均长度的概率
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24d1d79eceddd296b91a6ce25acc4bdb.png)
②纺织厂将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8b217a710338eab3bde4818ddd2c6dc.png)
y1 | y2 | y3 | y4 | y5 | y6 | y7 | y8 | y9 | y10 |
24.1 | 31.8 | 32.7 | 28.2 | 28.4 | 34.3 | 29.1 | 34.8 | 37.2 | 30.8 |
y11 | y12 | y13 | y14 | y15 | y16 | y17 | y18 | y19 | y20 |
30.6 | 25.2 | 32.9 | 27.1 | 35.9 | 28.9 | 33.9 | 29.5 | 35.0 | 29.9 |
若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0a4dfbe3fd17cbb8938052f1261185a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24d1d79eceddd296b91a6ce25acc4bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
月份 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
违法案件数 | 196 | 101 | 66 | 34 | 21 | 11 | 6 |
![](https://img.xkw.com/dksih/QBM/2020/4/8/2437146475782144/2437550805884928/STEM/2b3de3f68d884a499b6fd0655a1e7ef2.png?resizew=278)
(1)根据散点图判断,用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6a5b1c19e4c57f1d259f8269e551c64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fae94bfde7d5026813c16fd23e00d34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)根据(1)中的判断结果及表中所给数据,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
参考数据:
![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
62.14 | 1.54 | 945 | 36.186 | 140 | 346.74 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e19295641f44f5253dead61805ec8de1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44c9975f20200bbb8bff06c95388f954.png)
参考公式:对一组数据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaf1c6aadc0129bf86f4fff9dcfb924b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/154100371e025fffe0ffae8be9567383.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a14e40329de36fc4a1a3f8fbfafda12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2186481e5a3e999f662c3907b3303041.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81ff0671492cc8f5ae8faea92afb4c2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/09651f67-7ada-4353-a50b-54b9099f3b5c.png?resizew=247)
根据以上数据,绘制了散点图.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/f4afd332-1a4d-4848-842c-58a1e046b15e.png?resizew=147)
(1)根据散点图判断,在推广期内,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6a5b1c19e4c57f1d259f8269e551c64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a3edbe89f552dd6cfd1abd462eef371.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca31577dd76afbc1b720cdcad88ffd16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)根据(1)的判断结果及表1中的数据,建立
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(3)推广期结束后,车队对乘客的支付方式进行统计,结果如下
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/4ff79461-387e-4ffb-a8c8-5dcff822706d.png?resizew=261)
已知该线路公交车票价为2元,使用现金支付的乘客无优惠,使用乘车卡支付的乘客享受8折优惠,扫码支付的乘客随机优惠,根据统计结果得知,使用扫码支付的乘客中有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e6486784415f3537c9a13556c05d893.png)
![](https://img.xkw.com/dksih/QBM/2019/4/30/2193446774505472/2194398691180544/STEM/3ec489e1f7a447d8b8001b7e775be96e.png?resizew=7)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
参考数据:
![]() | ![]() | ![]() | ![]() | ![]() |
66 | 1.54 | 2711 | 50.12 | 3.47 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39ff66375b8e2c21f2695655cd804782.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44c9975f20200bbb8bff06c95388f954.png)
参考公式:
对于一组数据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/878207973fc87e9d7f523894b86453b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12214722e4fa6b2a66448df6bab6f041.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a14e40329de36fc4a1a3f8fbfafda12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/546482f27254887b7e9ffacdcc729c96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4768b3c15078c43b1503a4b1c90bdff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41452396e99b33ee1afd01f466809ad7.png)
(Ⅰ)活动开始后,一位参加者问:盒中有几张“五环”卡?主持人答:我只知道,从盒中抽取两张都是“会徽”卡的概率是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da989de1fdf0c5ca4475aade5b5e3631.png)
(Ⅱ)现有甲、乙、丙、丁四人依次抽奖,用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33470bee4febd946d39f7b63d6344c8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aeb49dbba01c4ff5f686ffc8828351b2.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/707ea658f3a9359f5740d5aab48f7948.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec2501478483e009e516bc18d70003af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33bd24e647a626899a243a3f3984f90a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9dd8bbf8d8b088f1df100e2347c351c3.png)
请写出函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)