Question

Var (x + 8) is
(a) var (8)
(b) var(x)
(c) 8 var (x)
(d) 0

Answer 1

var (X+ any constant ) = var(X)

thus var(X+8) = var (X)

thus option B is correct

general form
var(ax+b) = a²var(X)

Answer 2

Hi ,

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A discrete random variable X , the

variance of X is written as Var( X ).

Var( aX + b ) = a² Var( X )

Where , a and b are both constants.

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Now ,

According to the problem given ,

Var ( x + 8 )

= Var ( 1 × x + 8 )

Here , a = 1 , b = 8 ,

= 1² Var( x )

= Var( x )

Therefore ,

Option ( b ) is correct.

I hope this helps you.

: )