Mathematics · 2013
JEE Main · 22 April 2013, Shift 1 · Q65
Mean of 5 observations is 7. If four of these observations are 6, 7, 8, 10 and one is missing then the variance of all the five observations is:
Mean of $\displaystyle 5$ observations is 7. If four of these observations are $\displaystyle 6$, $\displaystyle 7$, $\displaystyle 8$, $\displaystyle 10$ and one is missing then the variance of all the five observations is :
Official answer
(1)
$\displaystyle 4$
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JEE Main 2013 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.