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Suppose we draw 3 balls without replacement from an urn with 2 red, 2 green, and 2 blue balls.

How can I find the probability of each 0 red, 1 red and 2 red? I know the number of sample space is 120 ( Since we draw 3 balls and 6 balls in total, it would be 6*5*4). But I'm not sure how to get 0 red probability and 1 red pro. and 2 red prob. Can someone please help me?

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    It says you're drawing *without replacement*, so if you stuck your hand in and grabbed three balls at once, what are the possible sets of colors you could get?2011-10-13
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    possible sets would be 120 cases.. isn't it?2011-10-13
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    That is one way to go about it. It depends on whether you treat each individual ball as distinguishable or not. Let's say you decide to take this approach. Consider the probability of getting zero red balls. Now, we're going to draw three balls in sequence. There are six balls in the urn. How many choices do you have for the first draw such that you don't draw a red one? Now there are five in the urn. How many choices do you have? Now, you're ready for the last draw. How many choices do you have? *So*...2011-10-13

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