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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

If the variance of the data 12 , 14 , 18 , 19 , 21 , 36 is λ , then the value of 3 λ is equal to

Correct answer

181

Step-by-step solution

x - = 120 6 = 20 The square of deviations about mean are 64,36,4 , 1,1 , 256 Variance, σ 2 = 362 6 = 181 3 = λ Hence, 3 λ = 181

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