Question

If the mean of Poisson distribution is $\frac{1}{2}$, then the ratio of $P(X=3)$ to $P(X=2)$ is

• A. 1:2
• B. 1:4
• C. 1:6
• D. 1:8

Answer 1

Answer: (C)

1:6

$P(X=3)/P(X=2)$
$=\frac{{\lambda }^3(2!)}{3!\left({\lambda }^2\right)}$
$=\frac{\lambda }{3}$
$=\frac{1}{2\left(3\right)}$
$=\frac{1}{6}$
The ratio is $1:6$