已知某市高三共有20000名学生参加二模考试,统计发现他们的数学分数
近似服从正态分布
,据此估计,该市二模考试数学分数
介于75到115之间的人数为( )
参考数据:若
,则
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be60e2fb52aadb9054eef5e1fa534bd1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
参考数据:若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c1ed67167078ea4f5f1ee53ee14164.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/657554cf215188af47de76874977c7f6.png)
A.13272 | B.16372 | C.16800 | D.19518 |
更新时间:2024-05-09 07:19:43
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