Instruction: Calculate the probability using combinations.
Context: This question tests the candidate's knowledge of complex probability calculations in the context of a popular card game.
Certainly, approaching a question like this, especially in the context of a Data Scientist role, provides an excellent opportunity to not only showcase my technical proficiency in probability theory but also my analytical thinking and problem-solving skills. Let me walk you through my thought process on how to solve this problem, which, in essence, is a great reflection of how I tackle data-driven challenges.
To determine the probability of getting exactly 2 aces in a 5-card poker hand, we need to break down the problem into more manageable parts and apply the concept of combinations. Combinations, in probability, are ways of selecting items from a collection, such that the order of selection does not matter. This is crucial in our case since the order in which the cards are drawn is irrelevant.
First, let's consider the number of ways to draw 2 aces out of the 4 available in a standard 52-card deck. This can be calculated using the combination formula, which is denoted as C(n, k) = n! / [k!(n-k)!], where n is the total number of items, k is the number of items to choose, and ! denotes factorial, the product of all positive integers up to that number.
For the aces, n = 4 (since there are 4 aces in a deck) and k = 2 (since we want exactly 2 aces). Therefore, the number of ways to choose 2 aces is C(4, 2) = 4! / [2!(4-2)!] = 6.
Next, we have to consider the remaining 3 cards in the 5-card hand, which should not be aces. Since there are 48 non-ace cards in the deck, the number of ways to choose 3 non-aces is calculated similarly by the combination formula.
For the non-aces, n = 48 and k = 3. Thus, C(48, 3) = 48! / [3!(48-3)!] = 17,296.
To find the total number of ways to get exactly 2 aces in a 5-card hand, we multiply the number of ways to choose the 2 aces by the number of ways to choose the 3 non-aces.
Therefore, the total number of ways = 6 * 17,296 = 103,776.
Lastly, to find the probability, we divide the total number of ways to achieve our specific hand by the total number of possible 5-card hands from a 52-card deck. The total number of 5-card hands is calculated as C(52, 5).
C(52, 5) = 52! / [5!(52-5)!] = 2,598,960.
The probability = Total number of ways to get exactly 2 aces / Total number of 5-card hands = 103,776 / 2,598,960 ≈ 0.0399.
To conclude, the probability of drawing a 5-card poker hand that contains exactly 2 aces is approximately 3.99%. This problem-solving approach—breaking down the problem, applying relevant mathematical concepts, and clearly communicating the solution—is indicative of the analytical skills and mindset I bring to the table as a Data Scientist. It’s a reflection of how I dissect data challenges, apply statistical methods, and derive insights that are both meaningful and actionable.