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Top Questions

14 votes
4 answers
931 views

What is the maximum number of people who speak only 1 language?

11 votes
2 answers
2k views

Signature doughnut from a city

17 votes
1 answer
1k views

Just the two of us

11 votes
2 answers
465 views

Is it possible to have a double miracle Sudoku grid?

4 votes
2 answers
474 views

Maximizing row and column products in a 4x4 grid

6 votes
2 answers
745 views

What is a Pisa Word™?

6 votes
1 answer
614 views

Determine if N is zibbable [closed]

10 votes
1 answer
409 views

"Shining Composer"

3 votes
3 answers
549 views

Knights, Knaves, and Spies

5 votes
2 answers
455 views

Can white checkmate in 1 move?

5 votes
1 answer
577 views

What were the last three single moves?

7 votes
1 answer
492 views

A Professor's Presentation

5 votes
1 answer
289 views

Swap the positions of the 4 chess knights

6 votes
1 answer
355 views

Impressions – a cryptic crossword

7 votes
1 answer
362 views

Colombian Sudoku, Cows and Bulls again…

4 votes
1 answer
311 views

Largest prime number erroneously erased when finding all primes less than 1000

2 votes
1 answer
182 views

Hold out to the bitter end

6 votes
0 answers
284 views

"Many tries will turn failures Ƨ successes"

8 votes
0 answers
152 views

Something above

0 votes
0 answers
174 views

Alternate 100 Blue Eyed Islanders Riddle Conclusion - Contradictory Laws

0 votes
1 answer
80 views

Identify the truth teller, the liar and the spy

-2 votes
1 answer
84 views

Can you use triangular tiles to form a rectangle of size 2016 cm by 2021 cm?

-3 votes
0 answers
120 views

Are the Polybius cipher and the Bifid cipher really easy to solve?

0 votes
2 answers
106 views

Weighing Coins -- a Different Approach

2 votes
1 answer
99 views

Circular Hedge Maze

1 vote
0 answers
91 views

Can black and white cooperatively put a stalemate to black in 16 moves (under ser-h conditions)?

0 votes
0 answers
70 views

In the rims of hell, A river flows

2 votes
0 answers
58 views

Whose turn is it?

4 votes
0 answers
56 views

The shortest way from A1 to B1


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