Q. 125.0( 1 Vote )

# If the standard deviation of a variable X is σ, then the standard deviation of the variable is

A. a σ

B.

C.

D.

Answer :

We have

Mean (X) =

We can write as: Mean (X) =

Mean (X) =

Var(X) =

Now, Substitute the value of y_{i}and Y, then we get

**Hence, Proved**

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