Four cards are randomly selected from a pack of 52 cards. If the first two cards are kings, what is the probability that the third card is a king?
2/50
This problem involves calculating a conditional probability, specifically the probability of drawing a third king from a standard deck of 52 cards, given that the first two cards drawn were kings. This scenario highlights the concept of dependent events, where the outcome of prior draws affects the possibilities for subsequent draws because cards are not replaced.
To solve this probability problem, it's crucial to understand the composition of a standard pack of 52 cards:
The question states that four cards are randomly selected. The key condition provided is that the first two of these selected cards are kings. We need to determine the probability that the third card drawn is also a king.
Before any cards are drawn, the deck is complete:
Since the first two cards drawn are kings, these specific cards are removed from the deck. This is a process of sampling without replacement, meaning the deck changes after each draw.
So, after the first two King cards have been drawn, the updated state of the deck for the next draw is:
Now, we need to calculate the probability that the third card drawn is a King, given the current state of the deck (50 total cards, 2 kings). The formula for probability is:
$$P(\text{Event}) = \frac{\text{Number of Favorable Outcomes}}{\text{Total Number of Possible Outcomes}}$$
For the third card to be a King:
Therefore, the probability that the third card is a King is:
$$P(\text{third card is a king}) = \frac{2}{50}$$
This calculation directly addresses the conditional probability based on the events that have already occurred.
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