A random variable $X \sim B(n, p)$, if values of mean and variance of $\mathrm{X}$ are 18,12 respectively, then $\mathrm{n}=$

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Aicharya · Accepted Answer

We have $n p=18$ and $n p q=12$ $\begin{aligned} & 	herefore \mathrm{q}=\frac{12}{18}=\frac{2}{3} \quad \Rightarrow \mathrm{p}=1-\frac{2}{3}=\frac{1}{3} \ & 	herefore \mathrm{n}\left(\frac{1}{3}ight)=18 \quad \Rightarrow \mathrm{n}=54 \end{aligned}$

A random variable $X \sim B(n, p)$, if values of mean and variance of $\mathrm{X}$ are 18,12 respectively,…

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