RRB Group-D Model Paper 18 with answers for online practice

We know that sum of first ‘n’ natural numbers = $\frac{\mathit{n}\left(\mathit{n}+1\right)}{2}$
∴ The average of first n positive integers = (n + 1)/2.
Finally, the average of first 100 positive integers = (100 + 1)/2 = 50.5