名校
1 . 阅读下面的材料:对于有理数
,
,我们定义符号
:当
时,
;当
时,
.例如:
,
.
根据上面的材料回答下列问题:
(1)
________.
(2)若
,则
的取值范围是________.
(3)当
时,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee9d48e670be1ddbfee3738824a7eccf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6a46e678bf9d2df5ad4c782b3dc22f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de72b9357e96546bc16a2e4859030535.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1132de2e8913dba9c5cc2396ecb09fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b65c0db4d91bca82c81077bcba31c71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f342cd12df732ed2c2f31c7f39d2bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f2ed5f167f370950461120a53fd2d5b.png)
根据上面的材料回答下列问题:
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1edc8b158b59cc51bbcc16cf4fc92d3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c41f8737454be9bbbb80086cc4074afa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(3)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/457fa3576b33f09c86dbf7c02f057bfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
您最近一年使用:0次
2 . 对非负实数x“四舍五入”到个位的值记为
,如
,
,根据你的理解完成以下问题:
(1)
______;
(2)若
,则实数x的最小整数是______
(3)已知
,求
的值..
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2efc4b458ea20c1acca4317505e9fd2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cedf029acacca6b9c16211f62a873210.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34c533e0e6838860f545bcb721edb94f.png)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b2a03824660309a1c46637251fd041.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a35ccc32aa3b95c885dbd1e08b65f721.png)
(3)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84fa59d33a5a3614f49060c574f6e7e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/857aeba8898ed5a6c27b1658fe366ccc.png)
您最近一年使用:0次
3 . 随着人们对健康的高度重视,水果已成为每个家庭的生活必需品.一名在校大学生抓住机会,利用“互联网+”自主创业,在网上销售
,
两种水果,今年一、二月份销售情况如表所示:(
,
两种水果的销售单价保持不变)
(1)求
,
两种水果售价分别是多少元/千克?
(2)若
种水果的进价为
元
千克,
种水果的进价为
元
千克,该大学生预计下个月用不低于
元的资金购进
,
两种水果共
千克(每种水果的进货数量必须为整数),且
种水果的数量不少于
种水果的两倍.
①问有几种进货方案,并写出其中进货资金最少的方案;
②为了回馈社会,支援山区,该大学生决定每销售一千克水果,爱心捐赠
元给某山区一所小学.假设每月购进的水果都能够全部销售,在进货资金最少的情况下,要使捐赠后最低获利
元,试求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
销售数量(千克) | 销售额(元) | ||
A种 | B种 | ||
一月份 | 300 | 100 | 5200 |
二月份 | 400 | 200 | 8000 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3304e23f3b0f9569c4140ca89b6498.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4333bb203d02814c146ed587b69ea69d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f43677db00ba65a7f96fc49627d70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4333bb203d02814c146ed587b69ea69d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02805e9cc99cfd2e00e978280594d1ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d0aac1830ede61d27561e5e93ccdc99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
①问有几种进货方案,并写出其中进货资金最少的方案;
②为了回馈社会,支援山区,该大学生决定每销售一千克水果,爱心捐赠
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a54fca607eeb8516ccc932569b0ed885.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
您最近一年使用:0次
名校
4 . 如图为小丽和小欧依序进入电梯时,电梯因超重而警示音响起的过程,且过程中没有其他人进出.已知当电梯乘载的重量超过300公斤时警示音响起,且小丽、小欧的重量分别为50公斤、70公斤.若小丽进入电梯前,电梯内已乘载的重量为x公斤,则满足题意的x的范围是______ .
您最近一年使用:0次
5 . 用甲乙两种原料配制成某种饮料,已知每千克的这两种原料的维生素C含量及购买这两种原料的价格如表所示:现配制这种饮料
,要求至少含有4200单位的维生素C,且购买原料的费用不超过72元.设所需甲种原料
,则可列不等式组为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/061a969859cacad7eb9988a587d6eaf8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f46957633f96181bafe91df537ed4fe.png)
原料 | 甲 | 乙 |
维生素 | 600单位 | 100单位 |
原料价格 | 8元 | 4元 |
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
2024-05-14更新
|
309次组卷
|
4卷引用:第十一章 一元一次不等式能力提升测试卷-2023-2024学年七年级数学下册《知识解读·题型专练》(苏科版)
(已下线)第十一章 一元一次不等式能力提升测试卷-2023-2024学年七年级数学下册《知识解读·题型专练》(苏科版)(已下线)第九章 一元一次不等式能力提升测试卷-2023-2024学年七年级数学下册《知识解读·题型专练》(人教版)(已下线)第04讲 一元一次不等式组(2个知识点+4类热点题型讲练+习题巩固)-【帮课堂】2023-2024学年七年级数学下册同步学与练(人教版)广东省深圳市蛇口育才教育集团2023-2024学年八年级下学期期中数学试题
6 . 某汽车专卖店销售
,
两种型号的新能源汽车.上周售出
辆
型车和
辆
型车,销售额为
万元.本周已售出
辆
型车和
辆
型车,销售额为
万元.
(1)求每辆
型车和
型车的售价各为多少万元?
(2)甲公司拟向该店购买
,
两种型号的新能源汽车共
辆,且
型号车不少于
辆,购车费不少于
万元,通过计算说明有哪几种购车方案?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13dfc625923e6fcb604f2b48aaf8445f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b765e032d24c1557ff29cb6f70be0a98.png)
(1)求每辆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)甲公司拟向该店购买
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8c4c029e552954bd493b49aeab82d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/110e329d74716ab387dc602bb2b4f998.png)
您最近一年使用:0次
7 . 某社区超市销售每套进价分别为200元和170元的
,
两种型号的餐具.近两周的销售情况如下表:
(进价、售价均保持不变,利润=销售收入-进货成本)
(1)求
,
两种型号餐具的销售单价;
(2)若超市准备用不多于5400元,不少于5340元的资金再次采购这两种型号的餐具共30套,求共有几种采购方案;
(3)在(2)的条件下,求超市全部售出这30套餐具后所获得的最大利润.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
销售时段 | 销售数量(套) | 销售收入(元) | |
|
| ||
第一周 | 3 | 5 | 1800 |
第二周 | 4 | 10 | 3100 |
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)若超市准备用不多于5400元,不少于5340元的资金再次采购这两种型号的餐具共30套,求共有几种采购方案;
(3)在(2)的条件下,求超市全部售出这30套餐具后所获得的最大利润.
您最近一年使用:0次
名校
8 . 根据以下素材,探索完成任务.
(1)求A、B型烟花每箱多少元?
(2)若该乡镇决定采购这两种型号的烟花共50箱,且购入的资金不少于8500元又不多于8800,则该乡镇共有几种购买方案?
(3)若该乡镇准备支出9000元(全部用完)购买这两种型号的烟花,可以燃放多少秒?
设计烟花采购方案 | |
五一假期即将到来,为了吸引更多的游客,某乡镇决定举办烟花节,需考虑如何采购烟花及烟花燃放时长. | |
素材1 | 已知一箱A型烟花比一箱B型烟花少100元,购买20箱A型和10箱B型烟花需要5500元. |
素材2 | 某烟花厂提供产品信息如下: (1)A型烟花每箱12发,B型烟花每箱20发. (2)本厂生产的所有型号烟花每发间隔5秒,且一发燃放完后另一发立即开始燃放. (3)燃放烟花时逐箱不间断燃放,且每次仅燃放一箱,假设每发烟花均能正常绽放,且间隔时长保持不变,忽略每箱烟花之间的引燃时间. |
(2)若该乡镇决定采购这两种型号的烟花共50箱,且购入的资金不少于8500元又不多于8800,则该乡镇共有几种购买方案?
(3)若该乡镇准备支出9000元(全部用完)购买这两种型号的烟花,可以燃放多少秒?
您最近一年使用:0次
2024-05-12更新
|
250次组卷
|
2卷引用:福建省厦门市集美区厦门市集美区灌口中学(福建省厦门第一中学集美分校)2023-2024学年七年级下学期期中数学试题
9 .
(
,
为常数,且
),我们称这种运算得到的结果是美丽数,记为
,其中
,
叫做美丽数对.当
,
均为正整数时,我们称
为正态美丽数,这时的
,
叫做正态美丽数的正态数对.
(1)根据以上理解填空,若
,则
_______,
________;
(2)已知
.
①求
,
的值;
②若
是正态美丽数,求满足
的正态数对有多少个?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/902d0237c586757474e76013a5725005.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03157293a87fe5865cabca6c45c801d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6d8a4cf957865fad1cb648fcd2cbaa0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6d8a4cf957865fad1cb648fcd2cbaa0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
(1)根据以上理解填空,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04846f1397cfe6490d2e19643bdd0966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5386d1040995ac58d4925549b5b2932b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c9bff9808086181d694e47ec3e4c475.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b517ab9db6d9b0fa9d8564402b00155.png)
①求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/124c48b1a28d3d900ac615589ffec7d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d866cdb2b0a1d33d41433a9dc1d323a.png)
您最近一年使用:0次
2024-05-11更新
|
108次组卷
|
2卷引用:安徽省六安市舒城县仁峰实验学校2023-2024学年七年级下学期期中数学试题
10 . 研学旅行继承和发展了我国传统游学“读万卷书,行万里路”的教育理念和人文精神,成为素质教育的新内容和新方式.某中学计划组织七年级师生赴某研学基地开展研学活动.现有A,B两种型号的客车,载客量和租金如表所示:
已知学校租用A,B两种型号的客车共10辆,租车的总费用不超过5800元.
(1)最多能租用多少辆A型号客车?
(2)若七年级师生共有480人,请写出所有可行的租车方案.
A型号客车 | B型号客车 | |
载客量(人/辆) | 50 | 45 |
租金(元/辆) | 600 | 520 |
(1)最多能租用多少辆A型号客车?
(2)若七年级师生共有480人,请写出所有可行的租车方案.
您最近一年使用:0次