Monty Hall
Definition · Level 11 · Interview practice
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Three doors, one car. You pick; the host, who knows where the car is, always opens a goat door and offers a switch. Switching wins 2/3 because your first pick was right only 1/3 of the time.
Example
With 100 doors and 98 opened, switching wins 99%.
Where Tradecraft teaches it
Level 11 · Interview practice, in the lesson “Probability & expected value classics”: The puzzles interviewers often recycle, and the five tools that crack them.
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