单价x(百元/个) | 30 | 35 | 40 | 45 | 50 |
日销售量y(个) | 140 | 130 | 110 | 90 | 80 |
(2)若每个健身器械的成本为25百元,试销售结束后,请利用(1)中所求的线性回归方程确定单价为多少百元时,销售利润最大?(结果保留到整数),
附:对于一组数据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eafbe64ec9acf78f3624abbd06d516e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1db6103cb0f1d2bd6b19235d53ee7e98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d508c6b821f5c82606c61d45ac2dd88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a6d7049b87d88cbe1e579e90ee42ef4.png)
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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6706fe00b4e231e62d9ecbec567d526b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09052719a6d55df23d74d8e3956257ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cc5bb6aabd9c9e2285f3f668c88ec9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
成本利润率 | ![]() | ![]() | ![]() |
概率![]() | 0.3 | 0.6 | 0.1 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
成本利润率 | ![]() | ![]() | ![]() |
概率![]() | 0.2 | 0.3 | 0.5 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
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/26b28c6b1f31a6c2836248baffb3af6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea83f19ebe778e1d3cc67b1a2839ab76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff8f8261e7e9522ded4a95798e22d9cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0091835d5056c48f7d0e7ccf33826cb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bd92afd0bb999b522105f9ce58f9b52.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fd4cc84f58a58d2ead895da231ce0b5.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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bf1efa7a4401504020bfca03f86fb17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8540acc0079971e4ca1a67af9d151089.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0e2308c842cf350c8dbd5d36e434b95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83641d7f3c8b55be87fdb92bba5efa4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d27eb5f46f2f5e3a8e747ce238658a.png)
![](https://img.xkw.com/dksih/QBM/2022/5/30/2990519343521792/2992114706497536/STEM/c4daec73-6143-411b-9eb1-4a1943945275.png?resizew=191)
(1)现在从抽样的100瓶消毒液中随机抽取2瓶二等品,求这2瓶二等品消毒液中其质量指标值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bf1efa7a4401504020bfca03f86fb17.png)
(2)若每瓶消毒液的生产成本为20元,特等品售价每瓶35元,一等品售价每瓶30元,二等品售价每瓶25元.政府指定该工厂5月份只生产10万瓶高考考场专用消毒液,要求高考考点使用特等品和一等品消毒液,剩下的二等品全部免费赠送给某区教育局用于各小学操场消毒.假定教育局全部购买了该厂5月份生产的特等品和一等品消毒液,估计该厂5月份生产的消毒液的利润(利润=销售收入-成本)是多少万元?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1926eb08a21a8b6558fcfd4c52a4a23b.png)
第一段生产的半成品质量指标 |
|
| |
第二段生产的成品为一等品概率 | 0.2 | 0.4 | 0.6 |
第二段生产的成品为二等品概率 | 0.3 | 0.3 | 0.3 |
第二段生产的成品为三等品概率 | 0.5 | 0.3 | 0.1 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/3/cf1c3022-ed7e-4704-8f02-e155731d0066.png?resizew=259)
若生产一件一等品、二等品、三等品的利润分别是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0efba7147f5b9ced8bc4a72f0a9fb8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b3779b4ea5477aebfe85113b0de1d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e052c58a4582f637cd0a927bce178e58.png)
(Ⅰ)以各组的中间值估计为该组半成品的质量指标,估算流水线第一段生产的半成品质量指标的平均值;
(Ⅱ)将频率估计为概率,试估算一条流水线一年能为该公司创造的利润;
(Ⅲ)现在市面上有一种设备可以安装到流水线第一段,价格是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22106fece16d6dbaa4e9ef5e0e950a4c.png)
(参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da0566989cb83aabc4d6c63d2de14195.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eb0c3c6d642b6ad7e1e6003cb74a2e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bce995dfca5907053853d80888916d9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/15/4159386f-ab06-4695-a425-e06979dbb66e.png?resizew=270)
(1)求这20天鲜虾的日销售量的平均值.
(2)该超市每天提供的鲜虾有罗氏虾和基围虾两种,假设接下来的几个月,每天提供的鲜虾总量为这20天日销售量的平均值,这两种虾的日销售率(某种虾当天的销量与该种虾当天供货量的比值)、进价、售价如下表:
日销售率 | 进价/(元/千克) | 售价/(元/千克) | |
罗氏虾 | 0.9 | 32 | 45 |
基围虾 | 0.95 | 24 | 32 |
单价x(元/件) | 8 | 8.2 | 8.4 | 8.6 | 8.8 | 9 |
销量y(万件) | 90 | 84 | 83 | 80 | 75 | 68 |
(2)若该产品成本是4元/件,假设该产品全部卖出,预测把单价定为多少时,工厂获得最大利润?
(参考公式:回归方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1db6103cb0f1d2bd6b19235d53ee7e98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36d2081b97f5469e1bb92c6f6c647be8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a58291bd91befe1061530246da983727.png)
中国新能源汽车产销情况一览表 | ||||
新能源汽车生产情况 | 新能源汽车销售情况 | |||
产品(万辆) | 比上年同期 | 销量(万辆) | 比上年同期 | |
2018年3月 | 6.8 | 105 | 6.8 | 117.4 |
4月 | 8.1 | 117.7 | 8.2 | 138.4 |
5月 | 9.6 | 85.6 | 10.2 | 125.6 |
6月 | 8.6 | 31.7 | 8.4 | 42.9 |
7月 | 9 | 53.6 | 8.4 | 47.7 |
8月 | 9.9 | 39 | 10.1 | 49.5 |
9月 | 12.7 | 64.4 | 12.1 | 54.8 |
10月 | 14.6 | 58.1 | 13.8 | 51 |
11月 | 17.3 | 36.9 | 16.9 | 37.6 |
1-12月 | 127 | 59.9 | 125.6 | 61.7 |
2019年1月 | 9.1 | 113 | 9.6 | 138 |
2月 | 5.9 | 50.9 | 5.3 | 53.6 |
![](https://img.xkw.com/dksih/QBM/2020/1/11/2374768754638848/2374897034043392/STEM/e1e06890d2344fd6bec97de501a99953.png?resizew=213)
根据上述图表信息,下列结论错误的是( )
A.2017年3月份我国新能源汽车的产量不超过![]() |
B.2017年我国新能源汽车总销量超过![]() |
C.2018年8月份我国新能源汽车的销量高于产量 |
D.2019年1月份我国插电式混合动力汽车的销量低于![]() |
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/3/6e154069-534e-4f68-ad86-6cf589639fe8.png?resizew=198)
A.这8个月销量的极差为4 132 |
B.这8个月销量的中位数为2 499 |
C.这8个月中2月份的销量最低 |
D.这8个月中销量比前一个月增长最多的是7月份 |