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RRB Junior Engineer / DMS / CMA 2019 · Question 2639 of 3719

Find the standard deviation of first 'n' natural numbers?

  1. A$$\sqrt{\frac{{n^{2}+1}}{6}}$$
  2. Bn$$(\frac{{n+1}}{12})$$
  3. C$$\sqrt{\frac{{n^{2}-1}}{12}}$$Correct
  4. D$$n(\frac{{2n+1}}{3})$$

Answer: C. $$\sqrt{\frac{{n^{2}-1}}{12}}$$

Official answer key verified. Detailed explanation coming soon.

Source: RRB JE 2019 CBT-1 (2-June-2019 Shift 2) — cracku.in solved paper with answer key · reliable-secondary

← Q2638View full paper (3719 questions)Q2640 →

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