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  1. What is the Arithmetic mean of the first ‘n’ natural numbers ?
    1. n(n + 1 )
      2
    2. n + 1
      2
    3. n2(n + 1 )
      2
    4. 2(n + 1)
Correct Option: B

As we know the formula for summation of n

Sum of first n natural numbers =
n(n + 1 )
2

∴ Required average =
n(n + 1 )
 =
n + 1
2 × n2


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