Target Exam

CUET

Subject

-- Applied Mathematics - Section B2

Chapter

Probability Distributions

Question:

Suppose that X has a Poisson distribution. If $P(X = 2) = \frac{2}{3}P(X = 1)$, evaluate $P(X = 0)$.

Options:

$e^{-2/3}$

$e^{-4/3}$

$e^{-1/3}$

$e^{-1}$

Correct Answer:

$e^{-4/3}$

Explanation:

The correct answer is Option (2) → $e^{-4/3}$

Given $P(X = 2) =\frac{2}{3} P(X = 1)$

$⇒\frac{e^{-λ}λ^2}{2!}=\frac{2}{3}\frac{e^{-λ}λ}{1!}⇒\frac{4}{3}$

Hence, $P(X = 0) = e^{-λ} = e^{-4/3}$.