I'm still having a bit of trouble trying to understand this stuff.

Source:Let a chip be taken at random from a bowl that contains six white chips, three red chips, and one blue chip. Let the random variable if the outcome is a white chip; let if the outcome is a red chip; and left if the outcome is a blue chip.

(a)Find the p.m.f. of

[snip]Probability and Statistical Inferences, 7E, by Hoggs and Tanis

I understand that , , and .

My issue here is determining a proper value for the numerator of my . My stab at this would be to say that the p.m.f. has the form of , where is the part I can't figure out.

I see a pattern though:

The difference between the first two terms is 3, and the last two terms is 2. Other than that, I'm at a standstill.

I'd appreciate any input!

--Chris

w00t!!! my 9th post!!