The variance of a set of numbers is 33. If each number is multiplied by -1 and then 1 is added to each number, What is the new variance ?A33B-33C34D-34Answer: A. 33 Read Explanation: σ=1nΣ(xi−x−)2=33\sigma=\frac{1}{n}Σ(x_i-\overset{-}{x})^2=33σ=n1Σ(xi−x−)2=33−xi+1-x_i+1−xi+1x−=Σ(−xi+1)n\overset{-}x=\frac{Σ(-x_i+1)}{n}x−=nΣ(−xi+1)=[−1nΣxi]+1=[-\frac{1}{n}Σx_i]+1=[−n1Σxi]+1=−x−+1=-\overset{-}x+1=−x−+1σ2=1nΣ[(−xi+1)−(−x−+1)]2\sigma^2=\frac{1}{n}Σ[(-x_i+1)-(-\overset{-}x+1)]^2σ2=n1Σ[(−xi+1)−(−x−+1)]2=1nΣ(−xi+1+x−−1)2=\frac{1}{n}Σ(-x_i+1+\overset{-}x-1)^2=n1Σ(−xi+1+x−−1)2=1n(xi−x−)2=33=\frac{1}{n}(x_i-\overset{-}x)^2=33=n1(xi−x−)2=33 Read more in App
