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Let `x_1, x_2, x_3, ,` be `n` values of a variable X. If these values are changed to `x_1+a ,x+2+a , , x_n+a ,where` a in R ,` show that the variance remains unchanged.

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we know that Variance will be changed if scale changes or both scale and origin changes
Variance won't be effected by change of origin and amplitude shiftng and thus variance remain unchanged.
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