Hi guzzlers,
Today’s puzzle concerns the Gunpowder Plot, in which Guy Fawkes and pals attempted to burn down the Houses of Parliament on this day in 1605. In an incident as yet unreported by historians, six men were rounded up by the authorities on suspicion of being traitors.
By chance the men had alphabetically consecutive names. Already very suspicious! The investigating officer took each of them aside and questioned them in private about the others. They made the following remarks.
Augustine: Felix is loyal, Erasmus is a traitor. Bartholomew: Augustine is loyal. Cuthbert: Felix is loyal, Bartholomew is a traitor. Dionisius: Cuthbert is loyal, Bartholomew is a traitor. Erasmus: Dionisius is a traitor. Felix: Augustine is loyal. It was known that loyalists tell the truth as far as they know it, so their comments about traitors can be trusted, but not their comments about loyalists. Traitors, on the other hand, know who is one of their own and who isn’t, and will always give false information. How many traitors are there? I’ll be back at 5pm UK with the answer and an explanation. PLEASE NO SPOILERS I keep the comments open because they are often funny and sometimes contribute interesting ideas about the mathematics behind the puzzles. But since I can’t stop smart Alecs writing the answer, if you want to solve the puzzle yourself DO NOT SCROLL DOWN! I set a puzzle here every two weeks on a Monday. I’m always on the look-out for great puzzles. If you would like to suggest one, email me. Todays puzzle is adapted from a question in the 2009 Australian Mathematics Competition, run by the brilliant Australian Mathematics Trust. It was written by Andrew Kepert. For more read TheGuardian
Augustine: Felix is loyal, Erasmus is a traitor.
Bartholomew: Augustine is loyal.
Cuthbert: Felix is loyal, Bartholomew is a traitor.
Dionisius: Cuthbert is loyal, Bartholomew is a traitor.
Erasmus: Dionisius is a traitor.
Felix: Augustine is loyal.
It was known that loyalists tell the truth as far as they know it, so their comments about traitors can be trusted, but not their comments about loyalists. Traitors, on the other hand, know who is one of their own and who isn’t, and will always give false information.
How many traitors are there?
I’ll be back at 5pm UK with the answer and an explanation.
PLEASE NO SPOILERS
I keep the comments open because they are often funny and sometimes contribute interesting ideas about the mathematics behind the puzzles. But since I can’t stop smart Alecs writing the answer, if you want to solve the puzzle yourself DO NOT SCROLL DOWN!
I set a puzzle here every two weeks on a Monday. I’m always on the look-out for great puzzles. If you would like to suggest one, email me.
Todays puzzle is adapted from a question in the 2009 Australian Mathematics Competition, run by the brilliant Australian Mathematics Trust. It was written by Andrew Kepert.
