Question

Weighted arithmetic mean of first n natural numbers

Answer 1

Answer:

Step-by-step explanation:

So you are taking the sum of n X n / W  

The weighted sum is the sum of the squares divided by W. The formula for the sum of the squares from 1 to n is n(n+1)(2+1)/6. That's a common formula, easy to look up, but you may not have seen it yet.  

So your answer is  

n(n+1)(2n+1)/6  

-------------------- = (2n+1)/3  

n(n+1)/2