Unanswered Questions
47 questions with no upvoted or accepted answers
22
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0
answers
3k
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What does this mathematical operator do?
The solution to this puzzle is one I came up with when working on this puzzle: What is the answer of this math puzzle?
For two natural numbers a,b, can you figure ...
- 660
22
votes
0
answers
2k
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REALLY important days in history
@Z. Dailey asks a mathematical puzzle Important days in history... and to come! with a series of dates in years 1973, 1978, 1983, 1992, 2005.
My puzzle asks the question: What is the previous date in ...
- 197
11
votes
0
answers
406
views
What is a Freecell Word™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with a special brand of Phrase™ and Word™ puzzles.
If a word conforms to a special rule, I call it a Freecell Word™.
Use the ...
- 11k
9
votes
0
answers
476
views
The highest poem
I am three, often a person, always a digit, and also witout.
George POUST was his name.
Manufactured by Ford between 1972 and 1976.
YMCA was not my first team in my coaching career.
Theory of ...
- 11k
8
votes
0
answers
229
views
There are 49 cards here. Figure out what the seven facedown cards are and what position they're in
So here's the problem
"There are 49 cards here. Can you figure out what the seven facedown cards are and what position they're in?"
I have tried about everything in my math tool belt to try ...
- 10.3k
7
votes
0
answers
397
views
Open the French safe
While walking in a small alley in Paris, you come across a safe.
The number pad looks like this :
There are things on the back of the safe too :
"À l'aide du carré 3x3 ci-dessous et des nombres ...
- 1,006
6
votes
0
answers
536
views
What is a Sharp Number™?
This puzzle is based off and inspired by the What is a Word™ and What is a Phrase™ series started by JLee and their spin-off What is a Number™ series.
This was originally going to be a challenge for ...
- 210
6
votes
0
answers
254
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Sequence puzzle: 3, 9, 27
A twist of the classic sequence game:
A friend asked me to find the rule to this sequence: 3, 9, 27.
I am allowed to suggest other sequences to test if they follow that (unknown to me) rule, to which ...
- 10.3k
6
votes
0
answers
511
views
Rare but Abundant in Hill and Hole
I am uncommon,
But a worthy goal.
Rare but abundant
In hill and hole.
Who am I?
You may already know the answer, so the task is not to answer the riddle per se, but to solve the following 'What is a ...
- 27.7k
6
votes
0
answers
218
views
What are the red, white, blue (and green) numbers?
Some numbers have been partitioned into $4$ groups. You must figure out how the numbers in each group are related, and what separates the groups.
Red: $1, 3, 4, 9, 13, 14, 15, 19$
White: $5, 7, 10, 12,...
- 148k
6
votes
0
answers
302
views
Find the missing element?
I've been trying to solve this for quite some time, can you help me solve it?
This puzzle was made by one of my friend's teachers. This is not copyrighted and cannot be found anywhere on the internet.
...
- 41.7k
5
votes
0
answers
223
views
"PRI" puzzle with line drawings, including some shapes
This is a "PRI" puzzle that was posted on a reddit question. https://www.reddit.com/r/cognitiveTesting/comments/1btdot2/has_anyone_got_any_hard_pri_puzzles/
- 10.3k
5
votes
0
answers
265
views
Longest Fibonacci word
Fibonacci words are defined as $F_0 = a, F_1 = b, F_{n+2} = F_nF_{n+1}$ where $a, b$ are letters. How can you find the longest Fibonacci sub-word in a given string?
Try to solve it in linear time ($O(...
- 151
5
votes
0
answers
337
views
You might dream about this puzzle
Find the pattern between these sets:
1: right, clocks, wings, hearted, yourself, strings
2: psychopath, bishop, withhold, breakthrough, shoplift, hopefully
3: bird, Vienna, tempt, modern, armadillo, ...
- 2,158
5
votes
0
answers
263
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The Jumbled Jaunts of Jormungandr
Jormungandr, the Snakebot of Doom has left New York. The world's armies and air forces have been decimated and cannot stop it. It has moved on from New York, and has flattened the following North ...
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