Use the associative property of addition to find the total of 1, 10, and 18 in two different ways.
a. 1 + 10 + 18 = 11 + 18 = 29; 10 + 18 + 1 = 28 + 1 = 29
b. 1 + 10 + 18 = 11 + 18 = 29; 18 + 10 + 1 = 28 + 1 = 29
c. (1 + 10) + 18 = 11 + 18 = 29; 1 + (10 + 18) = 1 + 28 = 29
d. (1 + 10) + 18 = 11 + 18 = 29; (10 + 1) + 18 = 11 + 18 = 29

step-by-step explanation:

b

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! )