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方差标准差

> 某学校有1000名九年级学生，要知道他们在学业水平考试中成绩为A等、B等、C等、D等的人数各是多少，需要做的工作是 A.求平均成绩 B.进行频数分布 C.求极差 D.计算方差

问题：

发布时间：2024-09-07

某学校有1000名九年级学生，要知道他们在学业水平考试中成绩为A等、B等、C等、D等的人数各是多少，需要做的工作是

A.求平均成绩
B.进行频数分布
C.求极差
D.计算方差

参考答案：

提问用户：5g***PH1

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