Solved cryptogram
Behind three doors sits one prize. Switching after a losing door opens doubles your odds.
Mathematics Facts, sourced to Wolfram MathWorld.
Solve it yourself
This fact is a cryptogram here: 73 letters over 20 different ones, graded hard.
Or go to the puzzle’s own page first.
What it means
Your first pick is right one time in three, and that never changes. So the other two doors hold the prize two times in three between them, and when the host, who knows where it is, opens an empty one, all of that weight lands on the single door left. Switching wins two thirds of the time. The puzzle famously drew thousands of angry letters, including some from mathematicians, when the correct answer was published in 1990.
The claim comes from Wolfram MathWorld.
- SourceWolfram MathWorld
- CollectionMathematics Facts
- Difficultyhard
- Length73 letters, 20 of them different
Nearby in the collection
The facts either side of this one.
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