A number of Knights and Liars went on a camping trip. Having pitched their tents for the night at the end of a long day's hike, Thomas (the best cook by far) settled down near the camp fire to make stew whilst everyone else sat in a circle around him, watching. Looking around, Thomas noticed that each person seemed to be sat between two people they knew, whereas Thomas himself knew no-one except his good friend Richard. So, getting everyone's attention, he asked a person at random in the circle the following question:

"You and the two people that are sitting next to you: Is there an odd number of Liars in that little group?"

The person replied. Thomas asked another person at random, and that person gave the same reply as the first. Again and again he asked and every time the reply was the same. Finally, having asked everyone else and always receiving the same reply, he turned to Richard and asked the question once more. Surprisingly, Richard answered differently to everyone else.

Thinking for a moment, Thomas asked Richard: "Are you sitting between two Knights?", to which Richard smiled and gave the same reply as he had previously.

Nodding, Thomas declared: "So, the Knights are outnumbered by the Liars here!", and turned back to making the stew once more.

If "n" people in total went on the camping trip, how many Knights and Liars are there, and what are Thomas and Richard?

(In reply to Okay - I have to ask by Nick Reed)

Thanks for the compliment, though I'm not sure I deserve it after allowing all of those mis-typings. I have tried devising original puzzles, but I am usually not happy with the results. I have just written a Knights/Liars puzzle I do like, assuming it is solvable. If I solve it, I'll post it here.

When I submit a previously published puzzle, I give credit to the original author when I can.

Posted by TomM on 2002-06-23 21:49:04