Two cards are drawn at random from a standard pack of 52 playing cards without replacement. What is the probability that both drawn cards are aces?
Aptitude
Probability
Difficulty: Medium
Choose an option
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A1/221
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B2/13
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C2/26
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DNone of these
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E—
Answer
Correct Answer: 1/221
Explanation
Introduction / Context:Card-draw probabilities often use combinations since order does not matter for the set of drawn cards. There are 4 aces in a 52-card deck; we want both drawn cards to be aces without replacement.
Given Data / Assumptions:
- Deck size = 52, aces = 4.
- Draw 2 cards without replacement.
Concept / Approach:
- Total unordered draws = C(52,2).
- Favorable draws (both aces) = C(4,2).
- Probability = C(4,2)/C(52,2).
Step-by-Step Solution:
C(4,2) = 6C(52,2) = 52*51/2 = 1326Probability = 6/1326 = 1/221Verification / Alternative check:Sequential method: P(first ace) = 4/52; P(second ace | first ace) = 3/51; product = (4/52)*(3/51) = 12/2652 = 1/221. Same result.
Why Other Options Are Wrong:
- 2/13 and 2/26 ignore shrinking deck or use wrong counting.
- “None of these” is false because 1/221 is exact.
Common Pitfalls:
- Using replacement probabilities or confusing ordered vs unordered counting.
Final Answer:1/221