First Ace at Card 14
Hint 1
The first 13 cards must be non-aces and card 14 must be an ace.
Hint 2
Think of it via order statistics: choose positions of the 4 aces among 52 cards.
Show worked solution
1. Reframe with combinations
The event happens if and only if exactly one of the 4 aces is in position 14, and the other 3 aces along with the choice of positions of all 4 aces among the first 13+the rest matter; equivalently, condition on positions of the 4 aces among 52 slots.
2. Direct combinatorial count
The first ace is at position 14 if and only if positions 1–13 contain no ace (all from the 48 non-aces) and position 14 is an ace. Equivalently choose the 3 remaining aces to be among the remaining cards.
3. Interpretation
This matches choosing which 4 of 52 positions hold aces, conditioned so that the smallest is position 14: the other 3 ace positions are chosen from the 38 positions after 14, and positions 1-13 are automatically non-ace.
Answer: C(38,3) / C(52,4)
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