# Poisson Distribution

• Apr 14th 2010, 05:54 PM
neverlosehope
Poisson Distribution
Can anyone help me to solve this problem ???

Waiting . . . . (Thinking)
• Apr 14th 2010, 06:47 PM
mr fantastic
Quote:

Originally Posted by neverlosehope
Can anyone help me to solve this problem ???

Waiting . . . . (Thinking)

In future, please type the question out.

Let X be the random variable 'number of bacterial colonies in a sample'.

X ~ Poisson($\displaystyle \lambda = 2$).

Calculate $\displaystyle p = \Pr(X \geq 1) = 1 - \Pr(X = 0)$.

Let Y be the random variable 'number of samples that have at least 1 bacterial colony in them'.

Y ~ Binomial(n = 4, p = see above).

Calculate $\displaystyle \Pr(Y \geq 1) = 1 - \Pr(Y = 0)$.
• Apr 14th 2010, 06:57 PM
neverlosehope
Thanks Mr Fantastic (Happy)
• Apr 14th 2010, 07:03 PM
neverlosehope
• Apr 14th 2010, 07:07 PM
mr fantastic
Quote:

Originally Posted by neverlosehope
X ~ Poisson(http://www.mathhelpforum.com/math-he...060384dc-1.gif).

Calculate http://www.mathhelpforum.com/math-he...62e81153-1.gif.

why we didn't write ut like this ???????

Calculate = 1-Pr(X<0)

What's the point? Can X be less than zero?
• Apr 14th 2010, 07:20 PM
neverlosehope
It's just a mistake , no it can't be less than zero

1-Pr (x<1) = 1-Pr(x=0)

U r Right sorry .

But are u sure we are gonna solve it by possion rule & binomial.

Can we just solve it by possion rule only ????
• Apr 15th 2010, 02:30 AM
mr fantastic
Quote:

Originally Posted by neverlosehope
[snip]
But are u sure we are gonna solve it by possion rule & binomial.

Can we just solve it by possion rule only ????

If you have so much doubt about the way I have shown you, please feel free to do it your own way.