Brain Teasers & Mental Math
The Monty Hall problem: 3 doors, a car behind one and goats behind the other two. You pick a door; the host (who knows what's behind them) opens a different door revealing a goat, then offers a switch. Should you switch?
Model answer
Yes — switching wins 2/3 of the time; staying wins only 1/3.
Your initial pick is right with probability 1/3 and wrong with probability 2/3. If you were wrong (2/3 of the time), the host is forced…
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