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        riddles >> easy >> Nights of the round table
        
(Message started by: BNC on Feb 3^rd, 2003, 9:00am)

Title: Nights of the round table
Post by BNC on Feb 3^rd, 2003, 9:00am

Around the round table are seated 18 people. Some of them are nights, and some are crooks. The nights always tell the truth (unless they are mistaken) and the crooks always lie.

Each of the 18 people claims to be seated between a night and a crook.

1. (easier): If none of the nights are wrong, how many nights are at the table?

2. (a little harder): If two of the nights are wrong, how many nights are at the table?

Title: Re: Nights of the round table
Post by Phil on Feb 3^rd, 2003, 9:55am

Both seem simple. I was going to suggest making it a little tougher still by having each person say, "Among the four people closest to me, 2 are nights and 2 are crooks."
But, strangely, both seating charts can stay the same.

Title: Re: Nights of the round table
Post by Icarus on Feb 3^rd, 2003, 6:45pm

There are 2 different numbers of Knights that solve question 1.
Question 2 precludes the 2nd possibility, however, so its number of Knights is unique.

Title: Re: Nights of the round table
Post by BNC on Feb 3^rd, 2003, 11:42pm

on 02/03/03 at 18:45:02, Icarus wrote:

There are 2 different numbers of Knights that solve question 1.
Question 2 precludes the 2nd possibility, however, so its number of Knights is unique.

If I understand your "2nd" possibility, let me state that I thought "some" means "more than 0". Is it wrong?

Title: Re: Nights of the round table
Post by Icarus on Feb 4^th, 2003, 4:21pm

Usually yes, but sometimes "some" is used to simply indicate the possibility. But I guess that usage is really bad grammar, so I will take it back and agree that 0 knights and 18 crooks is not a valid solution. Sorry about that. :-[