Mathematics · 2019
JEE Main · 11 January 2019, Shift 2 · Q86
A bag contains 30 white balls and 10 red balls. 16 balls are drawn one by one randomly from the bag with replacement. If X be the number of white…
A bag contains $\displaystyle 30$ white balls and $\displaystyle 10$ red balls. $\displaystyle 16$ balls are drawn one by one randomly from the bag with replacement. If X be the number of white balls drawn, then $\displaystyle \left(\frac{\text { mean of } X}{\text { standard deviation of } X}\right)$ is equal to :
Official answer
(3)
$\displaystyle 4 \sqrt{3}$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.