北京市燕山地区2024-2025学年第一学期七年级期中质量检测
数学试卷答案与评分参考 2024年11月
一、选择题(共20分,每题2分)
题号 1 2 3 4 5 6 7 8 9 10
选项 A D B B A D C C B D
二、填空题(共16分,每题2分)
11.1.7; 12.>; 13.-6,-16; 14.(答案不唯一);
15.; 16.; 17.,; 18.23,.
三、解答题(共64分,第19题16分,每小题4分;第20-21题,每题10分,每小题5分;第22-23题,每题5分;第24-26题,每题6分)
19.计算(本题满分16分,每小题4分)
解:(1)
=12-3-7 ········································2分
=2. ············· ···························4分
(2)
= ······· ·································2分
=-(6.5×2×3)
=-39. ········································4分
(3)
= ·········································2分
=-7. ········································4分
(4)
= ········································3分
=
=. ·········································4分
20.化简(本题满分10分,每小题5分)
解:(1)
= ··········································2分
= ··········································4分
=. ···········································5分
(2)
= ············································2分
= ·············································4分
=. ·············································5分
21.解方程(本题满分10分,每小题5分)
解:(1)
, · ············································2分
, ·············································3分
, ·· ···········································4分
. ··········································· ··5分
(2)
, ···············································2分
, ···············································3分
, ···············································4分
. ···············································5分
22.(本题满分5分)
解:
= ················································2分
=
= ··················································4分
当,时,
原式=. ··················································5分
23.(本题满分5分)
解:(1)-1, 1; ··················································2分
(2); ··················································4分
(3). ···················································5分
24.(本题满分6分)
解:(1) ···················································1分
=54km. ···················································2分
答:行程最多的一天比行程最少的一天多行驶了km.
(2) ·········································3分
=50+7÷7
=51 km. ··············································4分
答:这七天中平均每天行驶51km.
(3) ···············································5分
=752.76
≈753元. ············· ·································6分
答:小明家一个月(按30天计算)的汽油费用是元.
25.(本题满分6分)
解:(1)方案一: ·· ············ ·································1分
=
=元. ·· ············ ·································2分
方案二: ············ ·································3分
=元. ············· ·································4分
(2)当时,
方案一:元,
方案二:元.
∵36000>35200,
∴该中学选择方案二更省钱. ············· ·································6分
26.(本题满分6分)
解:(1) ①③ ; ············· ·································2分
(2) ; ············· ·································4分
(3)
=+
=+
=. ············· ·································5分
是对称式. ············· ·································6分
说明:与参考答案不同,但解答正确相应给分.北京市燕山地区2024-2025学年第一学期七年级期中质量检测
数学试卷 2024年11月
学校_________________ 班级________ 姓名________ 学号________
考 生 须 知 1.本试卷共4页,共三道大题,26道小题,满分100分。考试时间100分钟。 2.在试卷和答题卡上准确填写学校名称、班级、姓名和学号。 3.试题答案一律填涂或书写在答题卡上,在试卷上作答无效。 4.在答题卡上,选择题、画图题用2B铅笔作答,其他试题用黑色字迹签字笔作答。 5.考试结束,请将本试卷和答题卡一并交回。
一、选择题(共20分,每题2分)
第1-10题均有四个选项,符合题意的选项只有一个.
1.的相反数是
A. B. C. D.
2.下表是几种液体在标准大气压下的沸点:
液体名称 液态氧 液态氢 液态氮 液态氦
沸点/℃ -183 -252.78 -196 -268.9
则沸点最低的液体是
A.液态氧 B.液态氢 C.液态氮 D.液态氦
3.据统计,今年“十·一”小长假期间,近70 000人次游览了园博园“京彩灯会”.将70 000用科学记数法表示应为
A. B. C. D.
4.有理数a,b,c在数轴上的对应点的位置如图所示,则下列式子中正确的是
A. B. C. D.
5.已知是方程的解,则的值是
A.-3 B.-1 C.1 D.3
6.下列运算中,正确的是
A. B.
C. D.
7.如果,那么根据等式的性质,下列变形不正确的是
A. B.
C. D.
8.下面四个式子中,不能表示图中阴影部分面积的是
A. B.
C. D.
9.我国古代典籍《庄子·天下篇》中有这样一句话:“一尺之棰,日取其半,万世不竭”.现有一根长为1尺的木杆,第1次截取其长度的一半,第2次截取其第1次剩下长度的一半,第3次截取其第2次剩下长度的一半,…,则第99次截取后,木杆剩下的长度为
A.尺 B.尺 C.尺 D.尺
10.右图是某月的月历,现用“”图形在月历中框出5个数,
它们的和为55.不改变“”图形的大小,将“”图形
在该月历上移动,所得5个数的和可能是
A.40 B.88
C.107 D.110
二、填空题(共16分,每题2分)
11.用四舍五入法对1.654取近似数(精确到十分位)是 .
12.比较大小: (填“<”,“>”或“=”).
13.计算: , = .
14.请写出一个与为同类项的整式: .
15.一台电脑原价为a元,降价20%后,又降低m元,现售价为 元.
16.已知,则代数式的值为 .
17.观察下列代数式:,,,,,…,按照上述规律,第2024个代数式是 ,第个代数式是 .
18.计算机将信息转换成二进制数处理的,二进制即"逢2进1",如(1101)2表示二进制数,将它转换成十进制形式是1×23+1×22+0×21+1×20=13,那么将二进制数(10111)2转换成十进制是 ,将十进制数21转换成二进制是 .
三、解答题(共64分,第19题16分,每小题4分;第20-21题,每题10分,每小题5分;第22-23题,每题5分;第24-26题,每题6分)
19.计算:
(1) ; (2) ;
(3) ; (4) .
20.化简:
(1) ; (2) .
21.解方程:
(1) ; (2) .
22.已知,,求代数式的值.
23.如图,数轴上点A表示的数为a,点B表示的数为b,点C表示的数为c,其中b是最大的负整数,c是最小的正整数.
(1) b= ,
c= ;
(2)用“<”将a,,-c,c连接起来;
(3)点P为数轴上一动点,则的最小值为 .
24.随着人们生活水平的提高,家用轿车越来越多地进入家庭.小明家买了一辆小轿车,他记录了连续7天中每天行驶的路程(如下表,单位:km),以50 km为标准,多于50 km的记为“+”,不足50 km的记为“-”,刚好50 km的记为“0”.
第一天 第二天 第三天 第四天 第五天 第六天 第七天
-8 -11 -14 0 -16 +38 +18
(1)这七天中,行程最多的一天比行程最少的一天多行驶了多少千米?
(2)请求出这七天中平均每天行驶多少千米;
(3)若行驶100 km需用汽油6 L,汽油价为8.2元/L,请估计小明家一个月(按30天计算)的汽油费用是多少元?(结果保留整数)
25.为迎接新生,某中学计划添置100张课桌和把椅子.现经调查发现,某家具厂的每张课桌定价为200元,每把椅子定价为80元,而厂方在开展促销活动期间,向客户提供了两种优惠方案:
方案一:每买一张课桌就赠送一把椅子.
方案二:课桌和椅子都按定价的80%付款.
(1)用含的代数式分别表示方案一与方案二各需付款多少元?
(2)当时,通过计算说明该中学选择哪种方案更省钱.
26.阅读下面方框内的材料:
解答下面的问题:
(1)下列式子:①;②;③,其中是对称式的是 (填序号);
(2)写出一个系数为-2,只含有字母a,b且次数为6的单项式,使该单项式是对称式;
(3)已知,,求,并判断所得结果是否是对称式.