gmat og ds Is the standard deviation of the set of the measurements X1,X2 ,X3,X4.X20 less than 1)The variance for the set of measurements is 4.2)For each measurement,the difference between the mean and that measurement is 2
来源：学生作业帮助网 编辑：六六作业网 时间：2024/12/20 01:38:28
gmat og ds Is the standard deviation of the set of the measurements X1,X2 ,X3,X4.X20 less than 1)The variance for the set of measurements is 4.2)For each measurement,the difference between the mean and that measurement is 2
gmat og ds
Is the standard deviation of the set of the measurements X1,X2 ,X3,X4.X20 less than
1)The variance for the set of measurements is 4.
2)For each measurement,the difference between the mean and that measurement is 2
gmat og ds Is the standard deviation of the set of the measurements X1,X2 ,X3,X4.X20 less than 1)The variance for the set of measurements is 4.2)For each measurement,the difference between the mean and that measurement is 2
20个未知数的标准差小于3么?
1、这20个变量的方差是4
2、每个未知数和均值的大小相差2（比均值大2,或者小2）
对于一,方差是标准差的平方,方差是4,所以标准差是2,第一个可以判断
对于二,方差的定义是每个数和均值差的平方的期望
即DX=E（（X-E（X））²）,每个数都差2,所以 DX是4,标准差是2,可以判断
所以选择EACH那项
其实数学主要看prep和鸡精就行了,加油...
这组数 X1,X2 ,X3,X4....X20的标准偏差小于三吗？
1）这组数的方差是4，所以标准差是根4=2，小于三
2）每一个量，量与平均数之间的差值是2，所以方差等于2^2*20/20=4，所以标准差是2，小于3
是实际测量为x1，x2，X3的X4的.... X20的小于3的标准偏差？
1）设置为测量方差为4。
2对于每个测量），两者的均值和该测量相差2