自主录题
一
试题标签
省市校区
选择省
北京
上海
天津
安徽省
江苏省
湖北省
湖南省
河北省
浙江省
广东省
陕西省
山西省
甘肃省
福建省
青海省
辽宁省
江西省
重庆
吉林省
山东省
四川省
贵州省
河南省
云南省
海南省
黑龙江省
西藏自治区
广西壮族自治区
内蒙古自治区
宁夏回族自治区
新疆维吾尔自治区
香港特别行政区
澳门特别行政区
台湾省
请选择市
西安市
铜川市
宝鸡市
咸阳市
渭南市
延安市
汉中市
榆林市
安康市
商洛市
选择区域
全国
请选择学校
阶段科目
小学
初中
高中
语文
数学
英语
物理
化学
生物
政治
历史
地理
科学
信息
题型题类
解答题
综合题
基础题
必考题
易错题
压轴题
典型题
难典题
常考题
时政题
年份题源
2025
2024
2023
2022
2021
2020
2019
2018
2017
2016
同步
专题
复习
模拟
真题
联考
专练
月考
周考
期中
期末
单元
寒假
暑假
副题
请选择
存放类型
按考点
请选择
北师大版
人教新版
苏科新版
湘教新版
青岛新版
浙教新版
冀教新版
沪科新版
北师大新版
鲁教版（五四学制）
沪教版
北京课改版
人教版（五四制）
华东师大版2012
测试版
请选择
七年级上
七年级下
八年级上
八年级下
九年级上
九年级下
已选考点
难度系数
一星
二星
三星
四星
五星
在线训练
是
否
自主录题
一
试题内容
试题内容
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="line-height:150%"><span style="font-family:新宋体">小明的爸爸买了一个密码旅行箱，密码由六位数字组成．现小明爸爸已将密码的前四位数字确定为小明的生日（</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">1028</span></span><span style="line-height:150%"><span style="font-family:新宋体">），后两位数字由小明自己确定．小明想把十位上的数字设置为奇数，个位上的数字设置为偶数，且两个数位上的数字之和为</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span><span style="line-height:150%"><span style="font-family:新宋体">．这两个数位上的数字他采用转转盘的方式来确定，于是，小明设计了如图所示的两个可以自由转动的转盘</span></span><i><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">A</span></span></i><span style="line-height:150%"><span style="font-family:新宋体">和</span></span><i><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">B</span></span></i><span style="line-height:150%"><span style="font-family:新宋体">（每个转盘被分成五个面积相等的扇形区域）．使用的规则如下：</span></span></span></span></span><br /> <span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="line-height:150%"><span style="font-family:新宋体">同时转动两个转盘，转盘均停正后，记下两个指针所指扇形区域上的数（如果指针指到分割线上，那么就取指针右边扇形区域上的数）．若记下的两个数之和为</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span><span style="line-height:150%"><span style="font-family:新宋体">，则确定为密码中的数字；否则，按上述规则继续转动两个转盘，直到记下的两个数之和为</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span><span style="line-height:150%"><span style="font-family:新宋体">为止．请用列表法或画树状图的方法，求小明同时转动两个转盘一次，得到的两个数之和恰好为</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span><span style="line-height:150%"><span style="font-family:新宋体">的概率．</span></span></span></span></span><br /> <img height="141" src="/uploads/meth/20210108/834f6cee99b4287574ddf18c1a912c04.png" width="262" /><br />
题型种类
选择题
非选择题
选项效果
一行4选项
一行2选项
一行1选项
选项内容
A
B
C
D
E
F
G
H
选择答案
A
B
C
D
E
F
G
H
试题答案
答案详见解析
自主录题
一
试题解答
试题解答
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="line-height:150%"><span style="font-family:新宋体">解：列表如下：</span></span></span></span></span> <table class="Table" style="margin-left:19px; border-collapse:collapse; border:none"> <tbody> <tr> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:1px solid black; border-right:1px solid black; border-left:1px solid black" valign="top"> </td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:1px solid black; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">1</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:1px solid black; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">3</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:104px; padding:2px 2px 2px 2px; border-top:1px solid black; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">5</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:98px; padding:2px 2px 2px 2px; border-top:1px solid black; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">7</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:97px; padding:2px 2px 2px 2px; border-top:1px solid black; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span></span></span></span></td> </tr> <tr> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:1px solid black" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">0</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">1</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">3</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:104px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">5</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:98px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">7</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:97px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span></span></span></span></td> </tr> <tr> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:1px solid black" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">2</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">3</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">5</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:104px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">7</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:98px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:97px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">11</span></span></span></span></span></td> </tr> <tr> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:1px solid black" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">4</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">5</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">7</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:104px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:98px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">11</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:97px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">13</span></span></span></span></span></td> </tr> <tr> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:1px solid black" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">6</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">7</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:104px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">11</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:98px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">13</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:97px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">15</span></span></span></span></span></td> </tr> <tr> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:1px solid black" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">8</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:103px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">11</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:104px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">13</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:98px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">15</span></span></span></span></span></td> <td style="border-bottom:1px solid black; width:97px; padding:2px 2px 2px 2px; border-top:none; border-right:1px solid black; border-left:none" valign="top"><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">17</span></span></span></span></span></td> </tr> </tbody> </table> <span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="line-height:150%"><span style="font-family:新宋体">由表可知，共有</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">25</span></span><span style="line-height:150%"><span style="font-family:新宋体">种等可能结果，其中两个数之和恰好为</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span><span style="line-height:150%"><span style="font-family:新宋体">的结果数为</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">5</span></span><span style="line-height:150%"><span style="font-family:新宋体">，</span></span></span></span></span><br /> <span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="line-height:150%"><span style="font-family:新宋体">∴小明同时转动两个转盘一次，得到的两个数之和恰好为</span></span><span lang="EN-US" style="line-height:150%"><span style="font-family:"Times New Roman","serif"">9</span></span><span style="line-height:150%"><span style="font-family:新宋体">的概率为</span></span></span></span></span><img height="35" src="/uploads/meth/20210108/39021d2314c5e23948e1048c5d03f289.png" width="21" /><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="line-height:150%"><span style="font-family:新宋体">＝</span></span></span></span></span><img height="35" src="/uploads/meth/20210108/13572244922f5f790f521223ffacde3a.png" width="13" /><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri,sans-serif"><span style="line-height:150%"><span style="font-family:新宋体">．</span></span></span></span></span>
自主录题
一
试题点评
智能点评
使用智能点评模板
手动点评
本题考查了"列表法 "，属于"典型题"，熟悉题型是解题的关键
提交
提交
关闭