SOLUTION: A box contains 3 red and 5 green marbles. If 3 marbles are drawn without replacement, what is the expected number of red marbles?
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Question 247087: A box contains 3 red and 5 green marbles. If 3 marbles are drawn without replacement, what is the expected number of red marbles? Answer by edjones(8007) (Show Source):
You can put this solution on YOUR website! nCr=n!/((n-r)!r!) Combination of n things r at a time.
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If 56 draws of 3 marbles are done these are the expected results.
3 red: 3C3 = 1
2 red & 1 green: 3C2 * 5C1 = 15
1 red & 2 green: 3C1 * 5C2 = 30
3 green: 5C3 = 10
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Ed
