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Insidious Casino
Cards are revealed in pairs. A red–red pair goes to you, a black–black pair goes to the dealer, and a mixed pair is discarded. Can your final pile ever be larger?
Probability of winning
0%
The final piles always tie.
Try a random deck
52 cards remaining.
YOU
♥ Red–red pairs
0
cards collected
CURRENT PAIR
?
?
—
DEALER
♠ Black–black pairs
0
cards collected
Red cards seen0 / 26
Black cards seen0 / 26
Mixed pairs discarded0
Every mixed pair removes exactly 1 red + 1 black.
Recent pairs
RR → you · BB → dealer · RB → discard
No cards revealed yet.
Why you can never win
1
The deck starts balanced.
There are 26 red cards and 26 black cards.
2
Mixed pairs remove colors symmetrically.
If there are p mixed pairs, then exactly p red and p black cards are discarded.
3
The same number of each color remains.
red remaining = black remaining = 26 − p
4
Those remaining cards must belong to same-color pairs.
All remaining reds are yours; all remaining blacks are the dealer’s. Therefore both piles have exactly the same size.