1. ## Oreos

This should be simple but my 4 other people got a different answer than me.

You have a bag with 6 oreos. 4 are vanilla, and 2 are chocolate. You randomly pick 2 oreos from the bag.

Q: "What is the probability that the 2nd oreo is chocolate."

Since the prob that the 1st oreo is chocolate is 1/3, wouldn't the prob that the 2nd oreo is chocolate also be 1/3?

The 2 ways to get chocolate 2nd are "cc" and "vc", which I did below:

(2/6)(1/5) + (4/6)(2/5) = (2/30) + (8/30) = 1/3

Thanks
Hope this makes sense

2. ## Re: Oreos

Looks good.

Your method also can calculate probability that 2nd oreo is vanilla: "cv" or "vv"
(2/6)(4/5) + (4/6)(3/5) = 2/3

You can ask your other people to do their calculations for "2nd oreo is vanilla" and see if their answers are complementary.

3. ## Re: Oreos

I was disappointed that this thread wasn't just a discussion about how delicious oreos are.

4. ## Re: Oreos

Since you have no knowledge about the other picks, the "order" of picks is irrelevant.

i.e. The probability of 1st/2nd/.../nth oreos is chocolate is the same. It is simply 2/6.

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