Unit 12 · Multi-Step Conditional Reasoning
Three Doors — Which Statement Must Be True?
Lesson 29 of 30
About this lesson
Someone is hiding in one of three rooms. Each door has two statements — but at most one per door can be false. Room 2 breaks the rule immediately. Room 1 forces a name contradiction. Only Room 3 survives. This is pure case-elimination logic at its sharpest.
Chapters
Question
I am hiding in one of three rooms. On the door of each room I have written two statements, some true, some false. However, no more than one statement on each door is false.
| Room 1 | Room 2 | Room 3 |
|---|---|---|
| My name is Aziz | I am not in this room | My name is Luisa |
| I am not in this room | I am in Room 3 | I am not in Room 1 |
Which one of the following statements must be true?
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