Compute the probability of randomly drawing 5 cards from a deck and getting exactly 3 spades.

Answer 1

The probability of 3 S out of 5 cards picked is the product of choosing 3 S out of 13 S and 2 nonspades out of 39 nonspades divided by all the possibilities for 5 cards out of 52

P(3S out of 5 cds) = ₁₃C_{3 39}C₂ / ₅₂C₅ where _nC_k means the combination of n things k at a time.

.0815 is what I got.

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