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人数相等的甲、乙两个学校学生参加了同一次数学模拟测验,学校平均分和方差如下:=8...
人数相等的甲、乙两个学校学生参加了同一次数学模拟测验,学校平均分和方差如下:
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164040524827100/SYS201310221640405248271007_ST/0.png)
=80,
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164040524827100/SYS201310221640405248271007_ST/1.png)
=80,S
甲2=180,S
乙2=120,则成绩较为整齐的是( )
A.甲学校
B.乙学校
C.两学校一样整齐
D.无法确定
考点分析:
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