The variance is: S2 =1/n [(x1-m) 2+(x2-m) 2+...+(xn-m) 2].

Standard deviation: s = √ {1/n [(x1-m) 2+(x2-m) 2+...+(xn-m) 2]}

② If x 1, x2...xn, its variance is: s?

So the variance of kx 1, kx2...kxn is: k? s？

③ If x 1, x2...xn, its variance is: s?

Then the variance of x 1+a, x2+a, x3+a ... xn+a is: s? (No change)

(k 1, a is a non-zero constant)

④ If x 1, x2...xn, its variance is: s?

So the variance of kx 1+a, kx2+a, kx3+a ... kxn+a is: k? s？