On Friday I posted this puzzle….
There are four suspects, and one of them has committed a murder. They make the following statements, but only one of them is telling the truth. Who committed the murder?
Jon: James did it.
James: Bob did it.
Sid: I didn’t do it.
Bob: James is lying.
If you have not tried to solve it, have a go now. For everyone else the answer is after the break.
If Sid is innocent, then his statement is true and so the other three suspects are lying. But that means that Bob is also telling the truth, a contradiction. So Sid can’t be innocent and so he must be murderer.