Mean $= \frac{\sum_{i=1}^{n} i}{n} = \frac{n(n+1)/2}{n} = \frac{n+1}{2}$
Back to JEE Main 2021 Probability & Statistics
JEE Main 2021 — Mathematics Probability & Statistics
easy
mcq
2021
Official previous-year question
Verified 30 May 2026.
Question
The mean of the first $n$ natural numbers is:
Options
- A
$\frac{n+1}{2}$
- B
$\frac{n}{2}$
- C
$\frac{n(n+1)}{2}$
- D
$\frac{n-1}{2}$
Solution
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