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If the variance of the following data : 6 ,   8 ,   10 ,   12 ,   14 ,   16 ,   18 ,   20 ,   22 ,   24 is K , then the value of K 11 is

Correct answer

3

Step-by-step solution

The given data is : 6, 8, 10, 12, 14, 16, 18, 20, 22, 24 ∴ x ¯ = 6 + 8 + 1 0 + 1 2 + 1 4 + 1 6 + 1 8 + 2 0 + 2 2 + 2 4 1 0 = 1 5 0 1 0 = 1 5 The table is as below : x i x i - x ¯ x i - x ¯ 2 6 - 9 81 8 - 7 49 10 - 5 25 12 - 3 9 14 - 1 1 16 1 1 18 3 9 20 5 25 22 7 49 24 9 81 Total 330 Hence, Variance σ 2 = Σ x i - x ¯ 2 n = 3 3 0 1 0 = 3 3 . ​

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