Mathematics · 2020
JEE Main · 5 September 2020, Shift 2 · Q68
If the mean and the standard deviation of the data 3,5,7, a, b are 5 and 2 respectively, then a and b are the roots of the equation:
If the mean and the standard deviation of the data $\displaystyle 3,5,7$, a, b are $\displaystyle 5$ and $\displaystyle 2$ respectively, then $\displaystyle a$ and $\displaystyle b$ are the roots of the equation :
Official answer
(2)
$\displaystyle x^2-10 x+19=0$
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JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.