Target Exam

CUET

Subject

-- Applied Mathematics - Section B2

Chapter

Probability Distributions

Question:

The variance of Poisson distribution is 1. Then the probability that Poisson random variable X, takes the value equal to 2 is :

Options:

$\frac{1}{2e^2}$

$\frac{1}{2^2e}$

$\frac{e}{2}$

$\frac{1}{2e}$

Correct Answer:

$\frac{1}{2e}$

Explanation:

The correct answer is Option (4) → $\frac{1}{2e}$

The probability mass function (PMF) is,

$P(X=k)=\frac{λ^ke^{-λ}}{k!}$

Substitute $λ=1,k=2$

$P(X=2)=\frac{1^2e^{-1}}{2!}=\frac{1}{2e}$