Mathematics · 2019
JEE Main · 10 January 2019, Shift 1 · Q86
The mean of five observations is 5 and their variance is 9.20. If three of the given five observations are 1, 3 and 8, then a ratio of other two…
The mean of five observations is $\displaystyle 5$ and their variance is 9.20. If three of the given five observations are $\displaystyle 1$, $\displaystyle 3$ and $\displaystyle 8$, then a ratio of other two observations is:
Official answer
(2)
$\displaystyle 4$:$\displaystyle 9$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.