3.- In a certain desert region the average number of persons who become seriously ill each year from eating a certain poisonous plant each year is 3.2, determine what is the probability that at least 5 people will become seriously ill in two years (hint: this is a rare event and can be modeled using a Poisson distribution)

Using the pmf we can find the individual probabilities like this:

And replacing we got:

Step-by-step explanation:

Previous concepts

Let X the random variable that represent the number of people that will become sereiosly ill in two years. We know that

The probability mass function for the random variable is given by:

And f(x)=0 for other case.

For this case the value for would be:

For this distribution the expected value is the same parameter

On this case we are interested on the probability of having at least two chocolate chips, and using the complement rule we have this:

Using the pmf we can find the individual probabilities like this:

And replacing we got: