x‾=∑xin\overline{x}=\frac{\sum x_{i}}{n}x=n∑xi
Sx=∑(xi−x‾)2n−1S_{x}=\sqrt{\frac{\sum_{}^{}\left(x_{i}-\overline{x}\right)^2}{n-1}}Sx=n−1∑(xi−x)2