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        riddles >> hard >> The 100 cell Jail Riddle
        
(Message started by: RiddleGenius on Feb 23^rd, 2008, 12:33pm)

Title: The 100 cell Jail Riddle
Post by RiddleGenius on Feb 23^rd, 2008, 12:33pm

I'm not sure of my answer but i think its 10.

here are some examples....
cell one would only get visited once so it would remain open. Cell 9 would get visited 3 times so it would remain open. Cell 16 would get hit 5 times so that one would stay open. Cell 25 is another one that remains open, Cell 36, 49, 64,72,81, 100(1,9,16, 25)= 10 cell , mates free

Title: Re: The 100 cell Jail Riddle
Post by Icarus on Feb 23^rd, 2008, 12:49pm

~~Those are indeed the cells left open.~~ Do you know what is special about those numbers? It should help make it clear why they work. If not, think [hide]divisors[/hide].

See towr's reply for corrections.

Title: Re: The 100 cell Jail Riddle
Post by towr on Feb 23^rd, 2008, 12:53pm

72 looks a bit of an odd one out amongst the other open cells.
And it has an even number of divisers: 1,2,3,4, 6,8,9,12, 18,24,36 and 72
So it should be closed at the end.

There are 10 open cells at the end though.

Title: Re: The 100 cell Jail Riddle
Post by Icarus on Feb 23^rd, 2008, 12:55pm

Heh. I just saw he had some right, and didn't look close enough to notice either the ringer, or the cell he missed.

Title: Re: The 100 cell Jail Riddle
Post by RiddleGenius on Feb 23^rd, 2008, 1:12pm

yep its 4,