Mathematics · 2018
JEE Main · 15 April 2018, Shift 2 · Q87
If the mean of the data: 7, 8, 9, 7, 8, 7, λ, 8 is 8, then the variance of this data is:
If the mean of the data: $\displaystyle 7$, $\displaystyle 8$, $\displaystyle 9$, $\displaystyle 7$, $\displaystyle 8$, $\displaystyle 7$, $\displaystyle \lambda, 8$ is $\displaystyle 8$, then the variance of this data is :
Official answer
(2)
$\displaystyle 1$
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JEE Main 2018 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.