A crime has been committed and there are five suspects. Precisely one of the suspects is a knight and the remaining four are liars.
- Arthur said Dave did it, Dave said Bill did it, Bill said Cal did it.
- Cal said that he didn't do it and Eddie confessed that he did it.
- It is known that Arthur did not do it.
If precisely one of the suspects did it, who committed the crime?
Bill and Cal are saying opposite things, so one of them is the knight and one is a liar. Therefore, the other three are all liars. Since Arthur is a liar, Dave did not do it. Since Dave is a liar, Bill did not do it. Since Eddie is a liar, he did not do it. We know that Arthur did not do it. Therefore, Bill is the knight and Cal did it.
Posted by Math Man
on 2013-09-12 21:41:05