Can anyone clutch I need help with this math problem thanks :) (look at the photo)

2304

Step-by-step explanation:

a1 = 9

a2 = 4*a1 = 4*9 = 36

a3 = 4*a2 = 4*4*a1 = 4*4*9 = 144

a4 = 4*a3 = ... = 4*4*4*9 = 576

a5 = 4*a4 = ... = 4*4*4*4*9 = 2304

in other words

an = a1*4^(n-1)

you have to run through the calculation (in our case a simple multiplication by 4) n-1 times with the starting value of a1.

so, a5 = 9 * 4^4

for example a20 would then be

a20 = 9 * 4^19

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! )