MCQ
The arithmetic mean of 1, 2, 3, 4, ..., n is:
- A$\frac{n-1}{2}$
- B$\frac{n(n+1)}{2}$
- C$\frac{n}{2}$
- ✓$\frac{n+1}{2}$
✓
Answer
Correct option: D.
$\frac{n+1}{2}$
(d) $\frac{n+1}{2}$
Explanation: According to question,
Arithmetic Mean $=\frac{1+2+3+\ldots+n}{n}$
$=\frac{\frac{n(n+1)}{2}}{n}$
$=\frac{n+1}{2}$
Explanation: According to question,
Arithmetic Mean $=\frac{1+2+3+\ldots+n}{n}$
$=\frac{\frac{n(n+1)}{2}}{n}$
$=\frac{n+1}{2}$
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