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(2006•内江)若一组数据1,2,x,3,4的平均数是3,则这组数据的方差是(...
(2006•内江)若一组数据1,2,x,3,4的平均数是3,则这组数据的方差是( )
A.2
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131019110301274655296/SYS201310191103012746552006_ST/0.png)
C.10
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131019110301274655296/SYS201310191103012746552006_ST/1.png)
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