Algebra > Probability

Medium

applied

A random variable 'X' denotes the number of sixes obtained in three throws of a die. Then, the mean of the distribution is:-

$\frac{1}{3}$

$\frac{1}{2}$

$\frac{1}{8}$

$\frac{2}{3}$

✅ Correct Option: 2

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(A) For a random variable X, $E(X)=3$ and $E(X^2)=11$ , then $Var(X)$ is	(I) 25
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(C) In a binomial distribution, if $n=20, q=0.75$ , then its mean is	(III) 1
(D) If in a binomial distribution, mean is 5 and variance is 4, then the number of trials is	(IV) 5

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A random variable 'X' denotes the number of sixes obtained in three throws of a die. Then, the mean of the distribution is:-

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