1 . 二手车车龄与其价格之间是正相关,还是负相关?为什么?(古董车除外)
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2021-12-10更新
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140次组卷
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2卷引用:苏教版(2019) 选修第二册 名师导学 第九章 习题 9.1
名校
2 . 一个车间为了规定工时定额,需要确定加工某种零件所花费的时同,为此进行了6次试验,收集数据如下:
(1)在给定的坐标系中画出散点图,并指出两个变量是正相关还是负相关;
(2)求回归直线方程;
(3)试预测加工7个零件所花费的时间?
附:对于一组数据
,
,……,
,其回归直线
的斜率和截距的最小二乘估计分别为:
,
.
零件数x(个) | 1 | 2 | 3 | 4 | 5 | 6 |
加工时间y(小时) | 3.5 | 5 | 6 | 7.5 | 9 | 11 |
(1)在给定的坐标系中画出散点图,并指出两个变量是正相关还是负相关;
(2)求回归直线方程;
(3)试预测加工7个零件所花费的时间?
附:对于一组数据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56720e2f2b0ddd72156da495923698da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2852ae85cfcc804b3192ea8543c88938.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92abae836b8026511113ad8c3ea23028.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1db6103cb0f1d2bd6b19235d53ee7e98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0aa225ad36ee50c40869d87f694b6c54.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a58291bd91befe1061530246da983727.png)
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3 . 某超市为了解气温对某产品销售量的影响,随机记录了该超市12月份中
天的日销售量
(单位:千克)与该地当日最低气温
(单位:
)的数据,如下表所示:
求
关于
的线性回归方程
;(精确到
)
判断
与
之间是正相关还是负相关;若该地12月份某天的最低气温为
,请用
中的回归方程预测该超市当日的销售量.
参考公式:
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ebff20f21ae41fd8d1f1e3145895842.png)
参考数据:
,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d91e07104b699c4012be2d26160976a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1e8c29227443fdce7a5f66727f9ae77.png)
![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bf6c84731e5e1bd335ecfc2d36c3d81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/929ef3bed0a4bdd22f39e036506dc481.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/042e234d538bc2c789d7c5a314f1ca92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f53190d6ead827a6338b9de847aeaf1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d269d5f663fd6dea64baf9487400412.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bf6c84731e5e1bd335ecfc2d36c3d81.png)
参考公式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b34073ec2c46a4899f2dc7cf0a8075.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ebff20f21ae41fd8d1f1e3145895842.png)
参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b9d405bbed3992f19bbb099e58f80ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd661da617daebed3b8641acb90aef2d.png)
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2019-09-19更新
|
639次组卷
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3卷引用:广东省潮州市2018-2019学年高二下学期期末教学质量检测数学(文)试题
广东省潮州市2018-2019学年高二下学期期末教学质量检测数学(文)试题广东省潮州市2018-2019学年高二下学期期末教学质量检测数学(理)试题(已下线)8.1.1 变量的相关关系(分层作业)-【上好课】高二数学同步备课系列(人教A版2019选择性必修第三册)
真题
4 . 从某居民区随机抽取10个家庭,获得第i个家庭的月收入xi(单位:千元)与月储蓄yi(单位:千元)的数据资料,算得
,
,
,
.
(1)求家庭的月储蓄y对月收入x的线性回归方程y=bx+a;
(2)判断变量x与y之间是正相关还是负相关;
(3)若该居民区某家庭月收入为7千元,预测该家庭的月储蓄.
附:线性回归方程y=bx+a中,
,
,其中
,
为样本平均值,线性回归方程也可写为
.
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/f6aad3c722b247f8a377496372c521af.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/c320a21a443749439fcf51d1c3e121e8.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/dba0e4355d95474a980f2639b8b4e06d.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/1b7d9d8de25845b89036b3d8ffefc27f.png)
(1)求家庭的月储蓄y对月收入x的线性回归方程y=bx+a;
(2)判断变量x与y之间是正相关还是负相关;
(3)若该居民区某家庭月收入为7千元,预测该家庭的月储蓄.
附:线性回归方程y=bx+a中,
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/28f077dcb91649958914e58602c2ef21.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/391aca1bdea449eb9827c025f35bff93.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/059771293f034304a2b6d3691ab8639c.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/17c118b34b1c426cb86d52f7ff957e28.png)
![](https://img.xkw.com/dksih/QBM/2014/5/30/1571743652904960/1571743658598400/STEM/2faaae0bfedc45d5a1059c9670f0747f.png)
您最近一年使用:0次