1. ## Help! Poisson qns

1)At a fire station, each call out is classified as either genuine or false. Call outs occur at random times. On average there are 2 genuine calls in a week, one false call in a 2 week period. Calculate the probability that there are fewer than 6 genuine calls in a 2 week period.
(Ans:0.440)

my ans is 0.785.. This is my working.X~Po(4), P(X<=5) Why is it wrong?

2. So, X follows a Poisson distribution with $\lambda = 4$

$P(X<6) = \displaystyle \sum_{x=0}^5 e^{-4} \; \; \dfrac{\lambda^{x}}{x!}$

3. erh sry i dont understand your symbols.. is it that the correct ans given is wrong?

4. oo its alright now. the pictures did not appear just now. thanks!