名校
1 . 2020年,新冠状肺炎疫情牵动每一个中国人的心,危难时刻众志成城,共克时艰,为疫区助力.福建省漳州市东山县共101个海鲜商家及个人为缓解武汉物质压力,募捐价值百万的海鲜输送武汉.东山岛,别称陵岛,形似蝴蝶亦称蝶岛,隶属于福建省漳州市东山县,是福建省第二大岛,中国第七大岛,介于厦门市和广东省汕头之间,东南是著名的闽南渔场和粤东渔场交汇处,因地理位置发展海产品养殖业具有得天独厚的优势.根据养殖规模与以往的养殖经验,某海鲜商家的海产品每只质量(克)在正常环境下服从正态分布
.
(1)随机购买10只该商家的海产品,求至少买到一只质量小于265克该海产品的概率;
(2)2020年该商家考虑增加先进养殖技术投入,该商家欲预测先进养殖技术投入为49千元时的年收益增量.现用以往的先进养殖技术投入
(千元)与年收益增量
(千元).
的数据绘制散点图,由散点图的样本点分布,可以认为样本点集中在曲线
的附近,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0afe0652d1c6789c3694bec30dcfd860.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61c141cd1f61a4094965eed0dd30a7cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ea5b687d222752bc4c0524865595630.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a457bec5029ecead6084d2246ee4578e.png)
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4bbf744483137a8428a1b27659576c1.png)
,其中![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5a0edac1f5e98762f846cf9e534f75d.png)
.根据所给的统计量,求y关于x的回归方程,并预测先进养殖技术投入为49千元时的年收益增量.
附:若随机变量
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cce92eef8373f98d3859b00fb6f8c26a.png)
;
对于一组数据![](https://staticzujuan.xkw.com/quesimg/Upload/formula/878207973fc87e9d7f523894b86453b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6204602201419fcedb5abe57838fc707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66657c50fc7c11d98381748ad69a80a2.png)
,其回归线
的斜率和截距的最小二乘估计分别为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/468153cc737d66b7d168b901ca6085ea.png)
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c8b8de6d0c4904be5697e50df91c691.png)
(1)随机购买10只该商家的海产品,求至少买到一只质量小于265克该海产品的概率;
(2)2020年该商家考虑增加先进养殖技术投入,该商家欲预测先进养殖技术投入为49千元时的年收益增量.现用以往的先进养殖技术投入
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97ea8f47d8d8d9e1832d52b1c7425450.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4de122ae929b1acaff321dec137622ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b5f03c993304409c6bf36d9b3cff2a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c305c245407e2152ef4c582dc2d3f9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0afe0652d1c6789c3694bec30dcfd860.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61c141cd1f61a4094965eed0dd30a7cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ea5b687d222752bc4c0524865595630.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a457bec5029ecead6084d2246ee4578e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d202e40c117f844a8587690068a90711.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4bbf744483137a8428a1b27659576c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01ab5821fc1c2cca3cdf040151193bc3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5a0edac1f5e98762f846cf9e534f75d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79fb3265a6c81db8c6d36d5336bb5c0a.png)
附:若随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8867ec9d6b9de36bf61394ebe07cbb19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cce92eef8373f98d3859b00fb6f8c26a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8eabdfcbc03a1d0b223555af8dbf4315.png)
对于一组数据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/878207973fc87e9d7f523894b86453b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6204602201419fcedb5abe57838fc707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66657c50fc7c11d98381748ad69a80a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a14e40329de36fc4a1a3f8fbfafda12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0943f70585435955d528325e51ef013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/468153cc737d66b7d168b901ca6085ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/815e2869dc16e2ae7a7e1911e3afc8c3.png)
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2020-03-13更新
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4卷引用:山东省临沂市第一中学2019-2020学年高二下学期第三次阶段测试数学试题
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