So, I am having a problem with this in that the method I use gives two completely separate answers. Show
So, for the first method I reason this. The first card picked has a $13/52$ chance of being in some suit. The second card picked has probability $12/51$ of being in the same suit. So... The probability should be $(13/52)(12/52) = 3/52$. The other method is by combinatorics. I have $52 \cdot 51$ one ways of creating a pair of cards. But I have $13 \cdot 12$ different ways of creating a pair of the same suit. Now to me, the logical thing to do is to multiply this number by $4$, because I would have to count each valid pair from each suit. This would give me $$\frac{4 \cdot 12 \cdot 13}{52 \cdot 51}$$ What's wrong with the reasoning on the second one?
Two cards are draw at random from a well shuffled pack of 52cards. Find the probability that: The deck has cards of two colors: red and black. The probability to draw a black color is "\\frac{26}{52}=0.5" and the same is the probability to draw a red color. The probability that two cards have a red color is: "\\frac{26}{52}\\cdot\\frac{25}{51}\\approx0.2451". The same is the probability that two cards have a black color. We used the multiplication rule (https://www.statisticshowto.com/multiplication-rule-probability/) The probability cards have the same color is: "0.2451\\cdot2=0.4902". The probability that both cards have the different color is: "1-0.4902=0.5098" Answer: the probability that two cards have the same color is: 0.4902; the probability that both cards have the different color is: 0.5098. How many ways can 2 of the same cards be selected from a 52 card deck?There are 2,652 ways to pick two cards at random from a deck of 52 cards without replacing the first card before choosing the second card.
What is the probability of drawing an ace and a two from a deck of 52 cards without replacement )?WITHOUT REPLACEMENT: If you draw two cards from the deck without replacement, what is the probability that they will both be aces? P(AA) = (4/52)(3/51) = 1/221.
What is the probability that the 2 cards drawn have the same value?Therefore, the probability of drawing 2 cards of the same value is approximately 0.0588.
What is the probability that the top two cards of a standard shuffled 52 card deck have the same color both are red or both are black )?Two cards are drawn from a deck of 52 playing cards. What is the probability that both are red? 1/4 is the probability both are red.
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