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已知一组数据1、2、3、x、5，它们的平均数是3，则这一组数据的方差为（ ）
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一组数据3x0-1-3的平均数是1则这组数据的极差为．
已知数据x1x2xn的平均数是3则一组新数据x1+2x2+2xn+2的平均数是__.
已知一组数据x1x2x3x4x5的平均数是2方差是那么另一组数3x1－23x2－23x3－23x4－
一组数据24x-1的平均数为3则x的值是=_________.
有一组数据如下23a56它们的平均数是4则这组数据的方差是.
下列说法中正确的有1描述一组数据的平均数只有一个2描述一组数据的中位数只有一个3描述一组数据的众数只
1个
2个
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4个
已知一组数据35910x12的众数是9则这组数据的平均数是___________.
已知一组数据-2-23-2x-1的平均数是-0.5这组数据的众数是
-2
3
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1
已知一组数据a1a2a3a4a5的平均数为8则另一组数据a1+10a2-10a3+10a4-10a5
6
8
10
12
有一组数据如下23a56它们的平均数是4则这组数据的方差是.
已知一组数据624x5它们的平均数是4则这一组数据的方差为
1
2
3
4
一组数据含有三个不同的数:387它们的频数分别是352这组数据的平均数是_______.
已知一组数据―2―23―2x―1若这组数据的平均数是0.5则这组数据的中位数是___________
已知一组数据x1x2x3x4x5的平均数是2方差为那么另一组数据3x1-23x2-23x3-23x4
下面说法①如果一组数据的众数是5那么这组数据中出现次数最多的数是5②如果一组数据的平均数是0那么这组
1
2
3
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已知一组数据123x5它们的平均数是3则这一组数据的方差为
1
2
3
4
已知一组数据x1＝4x2＝5x3＝6x4＝7它们出现的次数依次为2321则这组数据的众数为中位数为平
一组数据123x5的平均数是3则该组数据的方差是
100
4
10
2
一组数据1325x的平均数为3那么这组数据的中位数是__________
有一组数据2356它们的平均数是4则这组数据的方差是.
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