单价x(元) | 8 | 8.2 | 8.4 | 8.6 | 8.8 | 9 |
销量y(件) | 90 | 84 | 83 | 80 | 75 | 68 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e3617671ab9daae844ca0a46066fe7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e3617671ab9daae844ca0a46066fe7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c85481cd7e94130ef3aa05b4a39e79cd.png)
(2)预计在今后的销售中,销量与单价仍然服从(1)中的关系,且该产品的成本是4元/件,为使工厂获得最大利润,该产品的单价应定为多少元?(利润=销售收入-成本)
月份 | 2020.02 | 2020.03 | 2020.04 | 2020.05 | 2020.06 |
月份编号![]() | 1 | 2 | 3 | 4 | 5 |
实际销量![]() | 0.5 | 0.6 | 1 | 1.4 | 1.7 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3f9a08ee8bc2746ce20df23b40fdb46.png)
(2)已知某地拟购买新能源汽车的消费群体十分庞大,某调研机构对其中的200名消费者的购车补贴金额的心理预期值进行了一个抽样调查,得到下表:
补贴金额预期值区间(万元) | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
频数 | 20 | 60 | 60 | 30 | 20 | 10 |
![](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/aefcbf930fe7ffbfeaba7f13cdba3884.png)
参考公式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97aea20ad446f9a61c72dc56031146ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
1 | 3 | 4 | 6 | 7 | |
5 | 6.5 | 7 | 7.5 | 8 |
![](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/2303bd7148062d66f25b02f690057d23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7f886f1c7dd2c27d0ed98984219a937.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/3/0a7d50a5-a908-4c8f-b305-d0a581c9339f.png?resizew=226)
(1)若农户卖出的该草莓的价格为150元/箱,试预测该水果100箱的利润是多少元.(利润=售价-成本)
(2)据统计,1月份的连续16天中农户每天为甲地可配送的该水果的箱数的频率分布直方图如图,用这16天的情况来估计相应的概率.一个运输户拟购置
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be604061cf1591f7069472269d4c9719.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fac3649308b528fd56545ba102dc42d5.png)
参考数据与公式:设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5a6bb3acdb5e690d71a5b15c5cc44bc.png)
0.54 | 6.8 | 1.53 | 0.45 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2303bd7148062d66f25b02f690057d23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d670cdf8ce3f59e43d7e87bbfa1d000.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![]() | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
![]() | 6 | 11 | 21 | 34 | 66 | 101 | 196 |
![](https://img.xkw.com/dksih/QBM/2020/9/25/2557559659208704/2557914965270528/STEM/5822a18f-9620-4816-adcc-d115d99719c1.png)
(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/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.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,结果如下表:
支付方式 | 现金 | 乘车卡 | 扫码 |
比例 | 10% | 60% | 30% |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e6486784415f3537c9a13556c05d893.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10b328845a4b1881eee38084d5501224.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
参考数据:其中
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39ff66375b8e2c21f2695655cd804782.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f9d52f1d64804b2eb844a8c91a8867b.png)
参考公式:对于一组数据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d5ba259eda554b5067243bb85eec269.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/25981f99d9f01b0845e8c5d5d03eea87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b194e2e65429c74167d24a7d687a039b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b83faa0e049032fbe6bd337273691657.png)
![]() | ![]() | ![]() | ![]() | ![]() |
66 | 1.54 | 2.711 | 50.12 | 3.47 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90dd550e1ad9bbf01687ffb4aab788ec.png)
![](https://img.xkw.com/dksih/QBM/2021/1/3/2628388949237760/2629077516083200/STEM/a3dabb63-b685-4695-8f33-212422632015.png)
(1)求a,并试估计这
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90dd550e1ad9bbf01687ffb4aab788ec.png)
(2)①由样本估计总体,结合频率分布直方图认为该产品的该项质量指标值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdd1128bad7312547877ee8b143e5607.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4825a8ebc51c830525cc7b48c52b177.png)
②国家有关部门规定每盒产品该项指标值不低于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a7afc6e67a875ed2eb889e950a77715.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4825a8ebc51c830525cc7b48c52b177.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2f7530034abc91d11bc847602eaf5bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/821d061d5114820074dd406b64a35c7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b184c94e38f1e5dbe750b2168c2a37.png)
等级 | 合格 | 优良 | 优秀 |
售价 | ![]() | ![]() | ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4bf051e3283d00f0b5a144f04ccb4a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a30f838de69af0b57785407f6f8ad4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3e6a1d2c14862178b0bdab168739423.png)
年份 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 |
广告费支出x | 1 | 2 | 4 | 6 | 11 | 13 | 19 |
销售量y | 1.9 | 3.2 | 4.0 | 4.4 | 5.2 | 5.3 | 5.4 |
(2)若用模型
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26a34dd2aaeb2144ea4d31339894b62e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b722f1ba18e869841aa381a50e9f0f6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85067c53e936ef32da818efe04bdbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85067c53e936ef32da818efe04bdbb.png)
(3)已知利润z(单位:万元)与x,y的关系为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66cc8763d08ef100567fd7316dba556b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14d21726b82e52bbd091c3d3279ba584.png)
参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c34f18776902797e3d506b4c0af69ef.png)
参考公式:线性回归方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a10cb9fd6d5c388cd9d28556d9e9dd8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ba6e95104c7ac77307befa26617046b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
年份 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 |
广告费支出 | 1 | 2 | 4 | 6 | 11 | 13 | 19 |
销售量 | 1.9 | 3.2 | 4.0 | 4.4 | 5.2 | 5.3 | 5.4 |
![](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/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26f8ec5fd4271341d105d5928c78bf88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28971de49e791d84eba87baa591fd261.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b2d48bbd01f2bf94a469bd29fb2c152.png)
(2)若用模型
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26a34dd2aaeb2144ea4d31339894b62e.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/c99a4d5fe26d3bc2a1eae0b8e9477288.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85067c53e936ef32da818efe04bdbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85067c53e936ef32da818efe04bdbb.png)
(3)已知利润
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66cc8763d08ef100567fd7316dba556b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14d21726b82e52bbd091c3d3279ba584.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8824e5d2981053b0473f658ba9001a11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/368763128d1ad0ffad5d859fef834d0a.png)
8 . 某超市计划按月订购一种酸奶,每天进货量相同,进货成本每瓶4元,售价每瓶6元,未售出的酸奶降价处理,以每瓶2元的价格当天全部处理完.根据往年销售经验,每天需求量与当天最高气温(单位:℃)有关.如果最高气温不低于25,需求量为500瓶;如果最高气温位于区间[20,25),需求量为300瓶;如果最高气温低于20,需求量为200瓶.为了确定六月份的订购计划,统计了前三年六月份各天的最高气温数据,得下面的频数分布表:
最高气温 | [10,15) | [15,20) | [20,25) | [25,30) | [30,35) | [35,40) |
天数 | 2 | 16 | 36 | 25 | 7 | 4 |
以最高气温位于各区间的频率估计最高气温位于该区间的概率.
(1)求六月份这种酸奶一天的需求量不超过300瓶的概率;
(2)设六月份一天销售这种酸奶的利润为Y(单位:元),当六月份这种酸奶一天的进货量为450瓶时,写出Y的所有可能值,并估计Y大于零的概率.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/738c2eb3b99133f96c55b643911d2f28.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fd7b7834f33ed54661f2ce4328f661a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eac97e6740365c85ad857aff85cefbe5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ee5447f1268cfd1949810ba8db48308.png)
(1)针对以上两个投资项目,请你为投资公司选择一个合理的项目,并说明理由;
(2)若市场预期不变,该投资公司按照你选择的项目长期投资(每一年的利润和本金继续用作投资),问大约在哪一年的年底总资产(利润+本金)可以翻一番?(参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/282724a3b2b45f1966a91389fdcedfcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb87d922f294f2696c2b12d2a7d2f8b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/254085ae2868cb0371a3844cac3fd14d.png)
最高 气温 | [10, 15) | [15, 20) | [20, 25) | [25, 30) | [30, 35) | [35, 40) |
天数 | 2 | 16 | 36 | 25 | 7 | 4 |
(1)求六月份这种酸奶一天的需求量X(单位:瓶)的分布列.
(2)设六月份一天销售这种酸奶的利润为Y(单位:元),当六月份这种酸奶一天的进货量n(单位:瓶)为多少时,Y的数学期望达到最大值?