The average of n numbers x1, x2, .... xn is x . Then the

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The average of n numbers x₁, x₂, .... x_n is x . Then the value of ⅀(x_i - x) , ( i = 1 .......... n ) is equal to

1. n
2. 0
3. nx
4. x

Correct Option: B

As we know that ,

x =	x₁ + x₂ + . . . .x_n
	n

= (x₁ - x) + (x₂ -x) +....... + (x_n - x)
= (x₁ + x₂ + . . . . . + x_n) - n . x

= n.		x₁ + x₂ + . . . .x_n		- n.x
		n

= nx - nx = 0