Question 671419
A standard poker deck of cards contains 52 cards, of which four are sevens. Suppose two cards are drawn sequentially, so that one random circumstance is the result of the first card drawn and the second random circumstance is the result of the second card drawn. Find the probability that the first card is a seven and the second card is not a seven. 
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# of ways to succeed: 4C2 = 6
# of possible outcomes: 52C2 = 1326
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P(2 7's) = 6/1326 = 0.0045
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Cheers,
Stan H.
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