Question

The standard deviation of 20 observations is √6. If each observation is multiplied by 3, findthe standard deviation and variance of the resulting observations.​

Answer 1

Answer:

3√6 ; 54

Step-by-step explanation:

N = 20 ; SD = √6

SD = √ [€ ( xi - M)^2] / N

now....each yi = xi × 3 = 3(xi)

also....M' = 3 × M = 2M

SD' = √ [€( 3xi - 3M)^2]/20

= 3 × [€( xi - M)^2] /20

SD'= 3 × SD

SD' = 3√6

Var' = (SD')^2

Var' = [3√6]^2

Var' = 54