Question:medium
If the mean of the first \(n\) odd numbers is \( \frac{n^2}{81} \), then \(n\) equals
If the mean of the first \(n\) odd numbers is \( \frac{n^2}{81} \), then \(n\) equals
Show Hint
Always remember:
\[
1+3+5+\cdots+(2n-1)=n^2
\]
This is one of the most frequently used formulas in aptitude exams.
Updated On: Apr 30, 2026
- \(9\)
- \(18\)
- \(27\)
- \(81\)
- \(52\)
Show Solution
The Correct Option is D
Solution and Explanation
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