The arithmetic mean of the squares of the first n natural numbers is

Options

A. `(n(n+1)(2n+1))/(6)`
B. `(n(n+1)(2n+1))/(2)`
C. `((n+1)(2n+1))/(6)`
D. `((n+1)(2n+1))/(3)`

Answer

C

Explanation

Sum of squares of first 'n' natural numbers
`=(n(n+1)(2n+1))/(6)`
Mean of the squares of first 'n' natural numbers
`=((n+1)(2n+1)xxn)/(6xxn)=((n+1)(2n+1))/(6)`