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two cards are drawn at random from a pack without replacement. what is the probability that the first is an ace and the second is a queen?

User Marlow
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2 Answers

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Final answer:

The probability that the first card drawn is an ace and the second is a queen, without replacement from a standard 52-card deck, is 1/663.

Step-by-step explanation:

To solve the probability question that two cards are drawn at random from a pack without replacement, and the first card is an ace and the second is a queen, we calculate the probability of each event occurring step by step and multiply them because the events are dependent.

The probability of drawing an ace first is 4/52 (since there are 4 aces in a 52-card deck). After drawing an ace, there are now 51 cards left. The probability of drawing a queen as the second card is 4/51 (since there are still 4 queens remaining, but only 51 cards).

So, the combined probability of drawing an ace first and a queen second without replacement is (4/52) × (4/51), which simplifies to 1/663.

User Hammad Nasir
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4 votes

Final answer:

The probability that the first card drawn is an ace and the second is a queen without replacement from a standard 52-card deck is 1/166. If identical cards are drawn, the sampling was with replacement. If there are no repeats in the drawn cards, then the sampling was without replacement.

Step-by-step explanation:

To answer the question about the probability that the first drawn card is an ace and the second is a queen when drawing without replacement from a standard 52-card deck, we must calculate the probability of each event occurring consecutively, without the first card returning to the deck. Initially, there are 4 aces and 52 cards in total. The probability of drawing an ace first is therefore 4/52. Once an ace is drawn, there are now 51 cards left in the deck, which includes 4 queens. The probability of then drawing a queen is 4/51.

The combined probability of both events happening in succession is found by multiplying the two probabilities together:

  • P(First card is an ace) = 4/52
  • P(Second card is a queen given first is an ace) = 4/51

The combined probability of drawing first an ace and then a queen without replacement is:

P(Ace first, Queen second) = P(First card is an ace) × P(Second card is a queen given first is an ace) = (4/52) × (4/51)

Computing this, we get the probability as:

P(Ace first, Queen second) = 16/2652

After simplification, this can be reduced to:

P(Ace first, Queen second) = 1/166

As for the information provided about drawing cards and determining whether the draws were with or without replacement, the following observations can be made:

a. If you draw the Q of spades, K of hearts, and then the Q of spades again, this implies that sampling must have been done with replacement, because the same card was drawn twice.

b. If you pick the K of hearts, then the three of diamonds, and finally the J of spades without seeing the same card twice, this suggests that the sampling was done without replacement.

User Sortofimport
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