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Mathematics

The Monty Hall Problem: A Counterintuitive Lesson in Conditional Probability

Quick fact

Studies show that when faced with the Monty Hall problem, most people stick with their original choice, yet the correct strategy is to switch, which gives you a 2/3 chance of winning the car, compared to just 1/3 if you stay.

Why this is interesting

You're on a game show, facing three doors. Behind one is a car; behind the others, goats. You pick a door, but then the host opens another, revealing a goat. He offers you a chance to switch. Should you? Most people say it doesn't matter—but they're wrong.