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  9. Q73

RRB NTPC 2021 · Question 73 of 131

Find the variance of the following data points: 6, 7, 5, 9, 12, 15

  1. A37/6
  2. B67/6
  3. C81/3
  4. D37/3Correct

Answer: D. 37/3

Explanation

6, 7, 5, 9, 12, 15 Mean = (5+6+7+9+12+15)/6 =54/6=9 6, 7, 5, 9, 12, 15 Deviation= 3, 2, 4, 0, 3, 6 Variance = (9+4+16+0+9+36)/6 =74/6 =37/3.

Source: RRB NTPC 2021 CBT 1 Previous Year Paper (3 Feb) — ixambee compilation with answer key · reliable-secondary

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