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Monty Hall Probability Lab

three doors, one car, two goats — and a counterintuitive answer

Pick a door — the car is behind one of them.

Your play record

Stayed

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0/0 wins

Switched

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0/0 wins

No Fibs — Honest Limitations

The Monty Hall result (switching wins 2/3) is mathematically certain under the classic rules — the host always opens a goat door and always offers the swap. Real game shows, and variants where the host behaves differently, change the answer. Your play record and best strategy save only in your browser.