# All Questions

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### Knights and Knaves: What does C say?

You are on a fictional island with two types of people: knights who always tell the truth, and knaves, who always lie. Three of the inhabitants - A, B, and C are standing in the garden. A says, "B and ...
138 views

### The best way to hire people

“We get a lot of applicants for our job vacancies,” said Lionel. He waved a hand in the general direction of the call-centre. “Here at Open to Everybody Insurance Services the jobs don’t need much ...
115 views

### Ewan, Ries, and Avut

There is a unique, well-defined word that completes the following quadruple: Ewan, Ries, Avut, ????. What's this word?
249 views

### What is a Commutative 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 Commutative Word™. Use ...
190 views

### Chess Construction Challenge #3-The Inverse Babson

Another day, another task! Today's challenge is to construct four positions, with White to move and win, such that: In each position, White's move is to promote to a particular piece, for a position ...
349 views

### Lost in time and space

You have been working on your plutonium-powered time machine for years, and now you finally succeeded! At least, you thought you did... After extensive testing with sending back and ...
612 views

### There's a snake lies

There's a snake lies. In the void must be filled. Hidden from the all conflict. Ever wonder what could have been. What/who am I describing? Hint 1: Hint 2: Hint 3:
499 views
+50

### Sharing cake among 9 or fewer people

You are expecting guests to your birthday party. You know that there will be at most 8 guests, but you don't know how many will actually come. What is the smallest number of pieces you should divide ...
2k views

### Smallest number containing the first 11 primes as sub-strings

113257 contains the first 6 primes as sub-strings when reading them from left to right: 2: 113257 3: 113257 5: 113257 7: 113257 11: 113257 13: 113257 What is the smallest number that contains ...
2k views

### An impressive body of work

To commemorate the 71st Primetime Emmy Awards being held today, here is a short and simple puzzle involving TV roles: Cersei Lannister, Game of Thrones Alexander Grayson, Dracula (2013) Bob Lee ...
727 views

### One-digit products in a row of numbers

The digits from 1 to 9 can be arranged in a row, such that any two neighbouring digits in this row is the product of two one-digit numbers. Arrangement: Is it possible to do such an arrangement ...
314 views

### Finish the sequence

1 $\to$ 4 $\to$ 6 2 $\to$ 3 $\to$ 7 19 $\to$ 16 $\to$ 11 8 $\to$ 14 $\to$ 12 15 $\to$ 17 $\to$ 19 18 $\to$ 13 $\to$ __
3k views

### I am not a pleasant sight

My prefix is round and mostly white My suffix is found in mines My infix is to say "right" I usually am an ugly sight What/Who am I?
123 views

### 2 IQ questions - what is the logic?

I was taking the test in the following link: https://testyourself.psychtests.com/bin/transfer But I am not really sure what is the answer and the logic behind them in the following questions: Do you ...
92 views

### How do you make 29 only using the numbers 1 2 3 4 [closed]

How do you make 29 with only using the numbers 1 2 3 4? I have tried a lot of solutions and please remember that you can't use the number 5
137 views

### Bake and share Fair and square

The chef ask each of the 4 judges to make a single slice on the whole round cake, so they'll all have a 1/5th piece to take. How the judges do it for fairness sake?
135 views

### Random IQ Matrix question

Found this picture in a random Whatsapp group. Someone said it's from one of the free online Mensa tests. Exact source unknown.
98 views

### Sudokus and combinatorics

Considering your suggestions, I have redrawn the 12 X 12 Sudoku so that the twelve rectangles are now visible. The question remains the same: Can someone construct a 12 X 12 Sudoku with the following ...
172 views

### Is there a limerick-style cryptic clue?

Is there a cryptic clue that happens to be a limerick? Please also include the answer in spoilers.
138 views

### IQ questions - Can you solve them?

Can you answer and explain the logic behind these questions? Source: https://similarminds.com/cgi-bin/int.pl
291 views

### Quick Yajilin Puzzles: Scatter and Gather

Yajilin (adapted from Nikoli) Draw a line to make a single loop. Lines pass through the centers of cells, horizontally, vertically, or turning. The loop never crosses itself, branches off, ...
315 views

### A family of movie lovers

In this family, each member has their favorite movies: Daniel: Interstellar, Top Gun, True Grit Deanna: The Fast and the Furious, Life of Pi, The Wizard of Oz Louise: Babe, Excalibur, Legion Michelle:...
105 views

### What is the pattern in the question box?

I am puzzled as to what pattern that should appear in the box with the question mark in the picture below. Can anyone solve this puzzle? If so, please explain why the solution is as it is.
223 views

### A delve into extraordinary chess problems: Selfmate 1

[This series continues from a harder puzzle here and continues in this puzzle] Here we have an easier but still interesting selfmate in 5. This is a puzzle by A. Rubin found in The Book of ...
275 views

### Hiker's Cabin Mystery | Pt. XVI

It's been a whiiiiiile since we've had one of these! You continue on through the forest and enter the labyrinth, once more. And again, you find a small piece of paper: ...
168 views

### Find the hidden message in this weird array

This puzzle is from my best friend. ? ? 0 ? ? ? ? ? 1 3 0 1 8 2 0 Figure out the answer. Do not ignore any of the tags! Hint:
259 views

### Line segments inside a square

A set of line segments inside or at the edge of a square with side length 1 should be positioned in such a way, that any straight line going through the square must touch or intersect at least one of ...
143 views

### Back in time, in my time, all the time

I present to you all a highly interesting problem that I came across awhile ago on Tim Krabbe’s site. It’s White move and win, i.e. reach a winning positon, in 21 moves. Source: David Gurgenidze &...
60 views

### Biuld a Box up Puzzle game [closed]

I want to build a box up puzzle game. I am struggling to implement this. Can you all suggest some sources or logic to implement it? Thanks in advance.
141 views

### What's the next step in this Unequal (Futoshiki) puzzle?

I'm currently stuck on this puzzle from Simon Tatham's website (he calls it "Unequal", although the standard name according to Wikipedia is Futoshiki). My progress so far is: I've even tried a few "...
158 views

### Piece de Resistance - Ten Quotas. Nine Passed. Your Turn

Ten Quotas. Nine Passed. Your Turn This puzzle is part of the "Piece de Resistance" series. Go back to Part 1 (Ace) for the story.Ace Two Three Four Five Six Seven Eight Nine Ten... Hmm... this is......
349 views

### Who/What am I? (The Five Ws)

I'm what stands between your family. I'm when your mind is set. I'm where your journey starts and ends. I'm why your story comes to life. Hint:
188 views

### What is an MM 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 an MM Word™. Use the ...
621 views

### Answering the Question of Life

Researchers from Ecuador knocked down an important obstacle in the road to a complete understanding of the human mind. "The initial plan to map specific areas of the human brain is 95% complete", Dr. ...
85 views

### What is a STATE Word™? [duplicate]

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 STATE Word™. Use the ...
102 views

### What is a BORE Word™? [duplicate]

In the spirit of the What is a Word™/Phrase™ series started by JLee, a special brand of Phrase™ and Word™ puzzles. If a word conforms to a special rule, we call it a BORE Word™. Use the examples ...
263 views

### Painting a 10x10 grid with 3 colours

Can you paint a 10x10 grid with 3 colours such that it doesn't contain any rectangles whose corners are all the same colour? Rectangles must be 2x2 or greater and parallel to the grid's sides. ...
1k views

### Painting a 4x6 grid with 2 colours

Can you paint a 4x6 grid with 2 colours such that it doesn't contain any rectangles whose corners are all the same colour? Can you do it without a computer? Rectangles must be 2x2 or greater and ...
254 views

### What is a DD Word™?

In the spirit of the What is a Word™/Phrase™ series started by JLee, a special brand of Phrase™ and Word™ puzzles. If a word conforms to a special rule, we call it a DD Word™. Use the examples below ...
290 views

### $4 \times 4$ Colorful Raven's Progressive Matrices

What will be the missing tile? The colorblind version is available here.
180 views

### A most delayed departure

My first is in Britain, which once was called Great, My second's in Boris, who's for sealing its fate. My third is in Europe, where patience wears thin, My fourth is in taxes, but not European! ...
231 views

### How to solve this cipher?

I'm given the cipher ESELUBRKXDBWTHARE and am told that it's a J. Bond quote. The only cryptography techniques I know are caesar ciphers and substitution ciphers. I learnt the vignere cipher after ...
248 views

### Find missing number in the transformation

Can you find the missing number? This number has a single digit. 8 → 7 7 → 3 3 → 5 5 → ? Good luck!
2k views

### The quicker I go up, the sooner I’ll go down - Riddle

I got this riddle (and a few more) from an old video game. I had a few ideas but none fit the entire riddle perfectly... The quicker I go up. The sooner I’ll go down. I’m a weave of edges, A ...
7k views

### Cut a cake into 3 equal portions with only a knife

You have to determine a way to cut a circular cake into exactly three portions of equal size. The only marking on the cake is a candle in the very center. All you have to work with is a knife that is ...
386 views

### Can you work out the word? (My original puzzle)

Help - the evil word splitter has been cleaving words in two with an evil curse! Fortunately, the word split in two can be reunited by saying its name correctly. But unfortunately, each half of the ...
232 views

### Next number in the sequence?

What is the next number in this sequence? 0, 6, 12, 19, 27, 35, 45, 54, 63, ? Good luck! HINT:
172 views

### Maximal sum in 5x5 Minesweeper

How can you place 8 mines on a 5x5 Minesweeper grid such that the sum of the produced numbers is maximal? Are there multiple solutions? Good luck with this!