Unit 6 · Identifying Sufficient Information
Door Code — Which Statements Are Sufficient?
Lesson 3 of 3
About this lesson
Three clues about a 4-picture code sequence leave exactly two possible arrangements — and they differ only in whether Bell or Book is at position 3 or 4. You get to ask one yes/no question. Which question gives a different answer in each arrangement, letting you uniquely deduce the code?
Chapters
Question
The code to open a door in a computer game is a sequence of four pictures in a row. You have found the following clues about the code:
The bell is next to the book. The apple is somewhere between the bell and the cat. The book is somewhere to the right of the cat.
You have to choose one of four possible questions to ask. When the question has been answered you must deduce the code.
Which one of the following questions would allow you to deduce the code?
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