Q12 / 77 · NTA Abhyas (JEE Main) 2020 · Mathematics · Statistics

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

Solution

$\bar{x} = \frac{120}{6} = 20$
The square of deviations about mean are $64,36,4, 1,1, 256$
Variance, $σ^{2} = \frac{362}{6} = \frac{181}{3} = λ$

Hence, $3 λ = 181$

Hence, the correct answer is 181.

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