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Mathematics · 2020
JEE Main · 7 January 2020, Shift 1 · Q68
An unbiased coin is tossed 5 times. Suppose that a variable X is assigned the value k when k consecutive heads are obtained for k =3,4,5, otherwise X…
An unbiased coin is tossed $\displaystyle 5$ times. Suppose that a variable $\displaystyle X$ is assigned the value $\displaystyle k$ when $\displaystyle k$ consecutive heads are obtained for $\displaystyle \mathrm{k}=3,4,5$, otherwise X takes the value -$\displaystyle 1$ . Then the expected value of X , is :
Official answer
(2)
$\displaystyle \frac{1}{8}$
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JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.