Question 870902: a deck of 20 cards is numbered 1 through 20 if two cards are selected at random without replacement what is the probability that both are even
Answer by jim_thompson5910(35256)   (Show Source):
You can put this solution on YOUR website! There are 10 even cards (2, 4, 6, 8, 10, 12, 14, 16, 18, 20) out of 20 total. So the probability that you pick an even card is 10/20 = 1/2.
On the second draw, you have 10-1 = 9 even cards left out of 20-1 = 19 cards total. So the probability of drawing another even card is 9/19.
Multiply them together: (1/2)*(9/19) = 9/38
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Final Answer: the probability that both are even is  (this is WITHOUT replacement)
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