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The absolute mean deviation about mean is 

The absolute mean deviation about mean is  Correct Answer Independent of change of origin

Explanation

Mean deviation about mean = (1/N)(∑I xi – x̅I        ------(i)

⇒ x̅ = a + ∑fdi/N

Put x̅ in equation (i) we get

⇒ MD = (1/N)(∑Ixi – (a + ∑fdi/N I

After shifting or changing the origin xi = di + a

⇒ MD = (1/N)(∑ I di + a – a - ∑fdi/N I

⇒ MD = (1/N)( ∑ I di - ∑fdi/N)

⇒ MD = (1/N)( ∑ I di – d̅ I

Which is independent of a

∴ Absolute mean deviation about mean is independent of change of the origin

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