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2024 年中考押题预测卷
数学·参考答案
第Ⅰ卷
一、选择题(本大题共8个小题,每小题3分,共24分.在每个小题给出的四个选项中,只有一项符合题
目要求,请选出并在答题卡上将该项涂黑)
1 2 3 4 5 6 7 8
A C B B D A D C
第Ⅱ卷
二、填空题(本大题共5小题,每小题3分,共15分)
9.
10.6
11.
12.-2
13.
三、解答题(本大题共13个小题,共81分.解答应写出文字说明,证明过程或演算步骤)
14.(5分)【详解】
····················································(3分)
.··································································(5分)
15.(5分)【详解】解:
····························································(3分).·································································(5分)
16.(5分)【详解】解:
···························································(3分)
··································································(4分)
经检验: 是原分式方程的解··········································(5分)
17.(5分)【详解】解:如图,点 即为所求.
··············································(5分)
18.(5分)【详解】 ,
,··························································(2分)
, ,
,···················································(4分)
.·····························································(5分)
19.(5分)
【详解】(1)解:由甲组对 四个小区进行抽查,则抽到B小区的概率是 ;(1分)
(2)画树状图为:
······························(4分)
共有12种等可能的结果数,其中甲组抽到C小区,同时乙组抽到D小区的结果数为1,
∴甲组抽到C小区,同时乙组抽到D小区的概率为 .·······················(5分)
20.(5分)【详解】解:所作 如图所示:
···········································(4分)
∴点 ;························································(5分)
21.(6分)
【详解】解:过C作 于H,
∴ ,
则四边形 是矩形,
∴ .
在 中,EA=3米,BE=5米,
∴ ,AB=4米,·····························(2分)
又∵ ,∴
∴ ,
∴ 米 ,
∴ 米,·························································(4分)
在 中,
∴ ,
∴ 或6.4米, ·································(6分)
答:匾额悬挂的高度是6.4米.22.(7分)
【详解】(1)解:根据图象知:大巴车行驶1小时后的速度为 千米/时;(2分)
(2)解: 由题意,设 ,···································(3分)
将点 、 代入,有
解得 ;···························································(6分)
∴函数表达式为 .·············································(7分)
23.(7分)
【详解】(1) 1班成绩中,得分为8分的出现了五次,出现的次数最多,
1班成绩的众数 ;················································(1分)
将2班20名学生的成绩从低到高排列,处在第10名和第11名的成绩分别为7分,7分,
2班成绩的中位数 ;···············································(2分)
1班成绩中,8分及以上人数为10人,
;··················································(5分)
(2) 人,
估计参加此次练习成绩合格的学生人数是99人.···························(7分)
24.(8分)
【详解】(1)证明:连接 交 于点 ,·····················································(1分)
,
且 ,········································(3分)
平分 ,
(2)解: 为 的直径,
,
是 的切线,
,
,
由(1)知, ,
四边形 为矩形,
,
,·······················································(5分)
在 中, ,
.
.
是 的中位线,
,
,·······················································(7分)
在 中, .································(8分)
25.(8分)
【详解】(1)解:∵矩形 中, 米, 米,
∴ 米, 米,∴ ,·
∴抛物线的对称轴为 ,
∴ ,····························································(2分)
设抛物线的解析式为: ,把 代入,得: ,
解得: ,························································(4分)
∴ ;··················································(5分)
(2)解:由题意,当 时: ,
解得: ,·······································(7分)
当 时, ,
∴ .···············································(8分)
26.(10分)
【详解】解:(1)∵ 是等腰直角三角形, ,
∴ , ,·····································(1分)
∵ ,即 .
∴ ,
∴ .·····················································(3分)
∴ , ,即 ;
∴ ;···················(5分)
(2) 长的最小值为 .
由题意,可知点 在以 为弦.所对圆心角为 的 上( ,则 ,劣弧 所
对的圆周角是 ).如图所示, .
∵ ,
∴ .···················································(7分)
连接 .当点 在线段 上时, 取得最小值,·························(8分)
如图所示,此时 .
∴ .
∴ 长的最小值为 .··········································(10分)