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Latest: A Black and White Issue (in Just Math) Rating: 1.00
In a 984 x 984 square grid, each square is colored either white or black. Each black square not on the border has exactly five white squares among its eight neighbors. Each white square not on the border has exactly four black squares among its eight neighbors. How many black squares are there?
 (No Solution Yet, 3 Comments) Submitted on 2013-06-18 by Danish Ahmed Khan
Bonus: The Last Dance (in Logic) Rating: 2.00
When Zablon asked how the last dance went, he got information from the four different people. Just like last year, the four people (Epotram, Forgam, Golkam, and Holdram) decided to mix up what they wore again, and together these four wore red, blue, green, and white of something. However, this year the four friends got tired of dancing earlier and each dropped out from dancing at a different time, such that only one of them made to the last dance. When Zablon asked four people about the last dance, each person told what he knew about what was asked. One of them was a liar; every one of his statements was a lie.

Z: What do you know about the person that was in the last dance?
A: I know the person with the white shirt wasn't in it. The person with the white shirt was the one that stopped right after the person with the red shirt.
Z: What else did you notice?
A: I know the person with the red shirt wore green suspenders.

Z: What do you know about the person that was in the last dance?
B:I know he wore blue suspenders, or that might have been the person that stopped first, I'm not sure. I do know that I looked at the people dancing when the person with the white shirt stopped, and there wasn't a person at all there that was wearing a red tie.
Z: What else do you know?
B:I know the person with the red tie didn't stop directly before the person with the red shirt. I remember Epotram wore only one thing that was red. Actually, I remember that two different people, the person with the white suspenders and the person with the white shirt, were talking to each other about the fact that nobody wore more than one thing that was red.

Z: What do you know about who stopped dancing last?
C: I know the person that stopped dancing second had something blue on. This person stopped dancing directly before or after Forgam. This means Forgam didn't stop dancing last.
Z: What else do you know?
C: Everyone liked to wear white for this, since it was snowing outside, and this meant nobody wore more than one white thing. Forgam eventually volunteered that the others could wear white things and he would not wear anything white.

Z: What do you know about who stopped dancing last?
D: I remember seeing Epotram, the person with the green shirt, and the person with the red tie, all three of them watching that person.
Z: What else do you know?
I know Golkam wore a white tie, but didn't wear anything blue.

(Solving notes: When B says "there wasn't anyone there at all wearing a red tie", he includes people outside the four people that the solution pertains to. If he's lying, you can't infer anything from that statement.)

(Note: When figuring the "lies" (where the inverse of everything that person says is true), don't count "story" elements. For example, when B says "I also know the person with the white suspenders and the person with the white shirt were talking to each other", if he was lying, it means the person wearing the white suspenders also wore the white shirt. The idea that B could be lying merely because these two people actually didn't talk to each other even though the person with white suspenders wasn't the person with the white shirt is disallowed.)
 (Solution Posted, 11 Comments) Submitted on 2004-02-04 by Gamer
Any others? (in Numbers)
Family Occupations (in Logic) Rating: 3.00
Posted on 2013-06-17 by K Sengupta (No Solution Yet, 2 Comments)
All bases comply (in Numbers) Rating: 2.00
Four Equal Triangles (in Geometry)
Posted on 2013-06-16 by Bractals (No Solution Yet, 3 Comments)
Divisibility of N (in Numbers)
Posted on 2013-06-15 by Jer (No Solution Yet, 3 Comments)
Introductions all around (in General) Rating: 3.00
Posted on 2013-06-14 by Danish Ahmed Khan (No Solution Yet, 4 Comments)
Jumbo Digits (in Just Math)
Posted on 2013-06-14 by Danish Ahmed Khan (No Solution Yet, 1 Comments)
Coin Toss (in Games)
Posted on 2013-06-13 by brianjn (Solution Posted, 3 Comments)
Mister Digit Face (in Just Math)
Posted on 2013-06-13 by K Sengupta (No Solution Yet, 1 Comments)
Vera's Date (in Logic) Rating: 4.00
Posted on 2013-06-12 by K Sengupta (No Solution Yet, 10 Comments)
Mouse eating Cheese (in Logic)
Posted on 2013-06-12 by Danish Ahmed Khan (No Solution Yet, 1 Comments)
Mail Delivery Muse (in Logic) Rating: 2.50
Posted on 2013-06-11 by K Sengupta (No Solution Yet, 3 Comments)
A G E S III (in Just Math) Rating: 2.50
Lion and Tamer (in Logic) Rating: 4.00
Posted on 2013-06-10 by Danish Ahmed Khan (No Solution Yet, 7 Comments)

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