Suppose each box of a popular brand of cereal contains a pen as a prize. The pens come in four colors: blue, red, green, and yellow. Each color of pen is equally likely to appear in any box of cereal. Reflect on all the devices we've used to simulate an experiment: fair coin, dice, spinners, bags of marbles, etc).

What device would you use to simulate the probability of drawing a blue pen from a cereal box? You must explain why you would choose this device.

answer: the answer is d

sweetheart, there isn't a cube below.

there is only one way to arrange all the eight relative to each other because they are not distinct. we have

now there are nine places to place an (and not more than one in one place).   because we have four symbols, we need to choose four of these nine places to insert an . order does not matter because the are not distinct.

thus there are 1 · c(9,4) ways, or, if we calculate it,

thus there are 126 ways to form such "words."