HardMath and Logic
Black win $1, Red lose $1. Quit anytime. Strategy?
Riddle
Black win $1, Red lose $1. Quit anytime. Strategy?
Choose an answer
A.Play until the end
B.Quit after first win
C.Always quit at 26 cards
D.Quit at positive EV
Hint: It's a 4-word phrase with 16 letters, starting with "Q".
Answer
Quit at positive EV
Why this is the answer
The expected value changes with every card drawn. If you have drawn more red than black, your chances of winning improve, and vice versa.
This riddle is filed under Expert Riddles for Adults and rated Hard.
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