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More of a logic problem, but strictly speaking, you could simplify this into boolean algebra which is math.
12 people say the following statements one after another:
#1: There are no honest people in this room;
#2: There is at most one honest person in this room;
#3: There are at most two honest people in this room
.. .. .. .. ..
#12: There are no more than 11 honest people in this room.
How many honest people are in the room?
"If I die of a heart attack eating bacon, I'll be a happy man." -My father
This post was edited by Hawkeye on Apr 06, 2006.
The statements are like this:
#1: There are at most 0 honest people in this room;
#2: There is at most 1 honest person in this room;
#3: There are at most 2 honest people in this room
#4: There are at most 3 honest people in this room
#5: There are at most 4 honest people in this room
#6: There are at most 5 honest people in this room
#7: There are at most 6 honest people in this room
#8: There are at most 7 honest people in this room
#9: There are at most 8 honest people in this room
#10: There are at most 9 honest people in this room
#11: There are at most 10 honest people in this room
#12: There are at most 11 honest people in this room
As you can see from the full list above - if you pick a person from the list and assume that he is honest, all following people must be honest (preceding persons are dishonest.)
The cutoff is at person 7, where there are 6 honest people. IF #6 where honest, you'd have 7 honest total, which contradicts #6's statement. If #8 and onward were honest, you'd have 5 honest, but that fails to meet the requirements of #6.
This is the official solution, but I would prefer one of my alternates - all of them are honest but have a false belief of what is true. :)