The variance of the first n natural numbers is [AMU 1994; SC

1.	The variance of the first n natural numbers is [AMU 1994; SCRA 2001]
A.	\[\frac{{{n}^{2}}-1}{12}\]
B.	\[\frac{{{n}^{2}}-1}{6}\]
C.	\[\frac{{{n}^{2}}+1}{6}\]
D.	\[\frac{{{n}^{2}}+1}{12}\]
Answer» B. \[\frac{{{n}^{2}}-1}{6}\]

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The variance of the first n natural numbers is [AMU 1994; SCRA 2001]

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