Sierra buys a bag of cookies that contains 9 chocolate chip cookies, 6 peanut butter cookies, 9 sugar cookies and 8 oatmeal raisin cookies.

What is the probability that Sierra randomly selects an oatmeal raisin cookie from the bag, eats it, then randomly selects another oatmeal raisin cookie?

Express your answer as a reduced fraction.

2/33

Step-by-step explanation:

First, add the amount of each kind of cookie to get the total amount of cookies(denominator), then add the amount of oatmeal raisins she pulled out(numerator)

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the answer   is 200

step-by-step explanation:

this is a problem about poisson probabilities.   i don't know if you've

already studied poisson distributions, or if you have a place to look

to read more about the subject.  

here's how you can see a poisson distribution coming.   when there are

a lot of events that may happen at any time (or any place), and when

you're counting how many of them happen at a particular time (or a

particular place), and each event is independent of the others, then

the result is a poisson distribution.   this is roughly true for the

chocolate chips; one chip being in a cookie has only a small effect on

the probability that another chip will be in the cookie.

once you know you have a poisson distribution, you know a lot.   there

is only one parameter to a poisson distribution, so if you know the

mean, you know everything.   the form of the distribution is

  probability of n chips = {[e^(-x)]*(x^n)} / (n! )

3.76%

step-by-step explanation: