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Monty Hall depends on what the host knows and does

Three doors hide one prize and two goats. Assume the prize is placed uniformly and the host knows its location, always reveals a goat behind an unchosen door, and always offers a switch. If two goat doors are available, the host chooses equally. Under those rules, switching wins in two of the three initial prize placements.

3–7 min

Questions you could explore

  • Why does an uninformed host who happens to reveal a goat create a different problem?
  • How do the host's rules change the information supplied by opening a door with a goat?

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