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Question
I found this question: Five cards are dealt from a standard deck of 52 cards.  What is the probability that three or four of the cards are aces?

I know probabilities very well, and this isn't that difficult of a question, but this one is stumping me up. Can you help?

Answer
In order to draw 3 aces you need to draw a 1st one, then a 2nd one, and then a 3rd one
So P (drawing 3 aces) = p(1)*P(2)*P(3) = (4/52)(3/51)(2/50) =1/5525
Now the P(drawing 4 aces) is the same except the 4th one after drawing the 1st 3 has a probability of 1/49
So  P(drawing 4 aces)= 1/5525* 1/49
Now the probability of drawing 3 or 4 aces follows
P(3)+P(4) minus P(3 intersect 4)= P(4)

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Sombra Shadow

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I can answer most questions up through Calculus and some in Number Theory and Abstract Algebra.

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