排列組合與機率統計(5)
Author: 藍邦偉　老師

法一

s^2=9=\frac{1}{9}\sum_{i=1}^{10}{ \left( x_i-7  \right)² }=\frac{1}{n-1}\sum_{i=1}^{n}{\left( x_i-\overline{x}  \right)²  }⇒\sum_{i=1}^{10}{ (x_i-7)²}=81

法二

法一

法二

$ s²=9=\frac{1}{9}\left(\sum_{i=1}^{10}{x_i^2 }-10×7²   \right) ⇒81=\sum_{i=1}^{10}{x_i^2 }-490⇒\sum_{i=1}^{10}{x_i^2 } =490+81=571$

n = 0 (slider from 0 to 10, step 1)
a = false
b = true
c = true
d = false