Mathematics · 2022
JEE Main · 30 July 2022, Shift 2 · Q89
The probability distribution of a random variable X is P(X=i)=1/2^i, i=1,2,3, … … …. The variance of X is equal to \ \ \ \.
The probability distribution of a random variable $\displaystyle X$ is $\displaystyle P(X=i)=\frac{1}{2^i}$, $\displaystyle i=1,2,3, \ldots \ldots \ldots$. The variance of $\displaystyle X$ is equal to \_\_\_\_.
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JEE Main 2022 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.