# All Questions

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### humans, vampires and mirrors

Here is a room composed of $10 \times 10$ squared cells. Some cells contain a double-faced mirror ( / or \ ) that reflects the light with an angle of $90°$ on both sides. The other cells can be empty (...
61 views

### Pretty lame reviews.. Why do people want this?

Browsing an online store, you see this product. The reviews are pretty low, but it seems many people want it. What is it ?
191 views

### Let's Play Tetris!

Fill the whole grid with Tetrominos. Every cell must be part of exactly one Tetromino. Tetrominos can be rotated as necessary. The colored clue cells must be part of the indicated type of ...
61 views

### Analogy with Number

The given analogy is 343 : 989 :: x : 669 What is x? 223 332 333 233
65 views

### Elementary, my dear Louis

Felt it was time for another Density™ puzzle. Warning: May require thinking. Enjoy! Final answer: (3,4,4,4)
69 views

### Find missing number

In below grid there are 2 numbers missing fill it with appropriate number . Text version: 69 10 13 192 ? 45 279 64 ? Hint :
108 views

### Mosaic by Albrecht Dürer

This is a visual puzzle (known as "mosaic" or "fill-a-pix") with the same rules as MineSweeper: The grid is to be filled with colored and white tessera. Choose whatever color you like for the colored ...
209 views

### 4x4 Grid with multiple solutions

Consider the following 4x4 grid : 972 9 5 55 18 22 x 28 50 24 25 26 7 400 52 4 Find x. However, as the title suggests, there are multiple solutions. You have to ...
305 views

### Could they have avoided it?

Weird undiscovered disease slams twins equally. Did they catch it in Lyon, Turin or Barcelona? Hint Hint 2
424 views

### Phoebe's favorite insect

If Charity wants to be happy on Mondays, If Mark's thing falls into water, and if Velma eats fruits with her fingers, What would Phoebe's favorite insect be ? Hint Hint 2
40 views

### Where is Bob tweeting from?

Your friend Bob burnt out at his job, and went abroad for a long vacation1. He tweeted this today. Where is he ? 1 Note that Bob is not subject to lockdown since he is as hat.
346 views

### What do they all mean?

Middle names of two pres'dents, and one of a time traveler, A most famous sorceress, and a programmer's laughter. A call for assistance, an invisible juncture. What do they all mean? (...
143 views

### Is my colleague happy with me?

So I graduated last year with a chemical degree and I started working in a lab. I'm still pretty nervous about making mistakes, so when I had to prepare a tricky experimental setup, I wrote down what ...
1k views
+50

### Check my drawing skills!

I was never too good at drawing, but...if this is the case, there is a word associated with this bmp image. Find out which one. hint hint2 Hint3 Hint4
61 views

### How many spots do these frogs have?

You are approached by 5 spotted frogs who appear to be venomous, to avoid getting bitten by them, you must find out how many spots they have. The frogs with an even number of spots always tell the ...
283 views

### Tokyo Metro puzzle #4

Yet another Tokyo Metro puzzle based on the map! Puzzles 1, 2, and 3 are avaliable. Riddle: ...
326 views

### What is the minimum count of steps required to complete this maze correctly?

Here's a map: How to play Legend: B = Boost X = Objective (•) = ...
144 views

### That letter sequence started so nicely

Find out how the following letter-sequence is constructed: ...
256 views

### Make the numbers 1-50 using the digits 2, 0, 2, 0

Try to make all the numbers from 1-50 using 2, 0, 2, 0 exactly once. Rules: Use only the operations +, -, *, /, !, exponents and square root No rounding eg. ...
164 views

### Number Guessing (Part 1)

I thought up two numbers with product less than $500$. I told their product to Penny, and their sum to Sandy, and told both of them the constraints and they are both perfect logicians. They have ...
237 views

### Tokyo metro puzzle #5

This is based on the first, second, third, and fourth. It will be the finale of the series. It relies on the answers to the previous four. Takebashi (solved by Nick & Brandon_J) ??? Ikebukuro (...
170 views

### Three riddles in one

Look at the conversation below Mary: Oh no! My ___________! John: _________ happened? Mary: I don't know! John: You're REACTing too much, EH? Clue 1: The answer is three words, but if ...
279 views

### The Alchemist goes missing

He hadn't been responding to emails for days. When he was deeply involved in his work, delays were not uncommon, but not this long. Something was clearly amiss. Something had happened to my long time ...
90 views

### My friend's next country

My friend gave me this puzzle. Here is the list of the places I went to, in this particular order, and their scores. United States (USA) 1890.19 Soviet Union (URS) 860.14 France (FRA) 749.02 ...
375 views

### A trip around the United States

My journey so far has taken me to the following cities in order: New York (where I started from), Baltimore, Cincinnati, Sioux City, Monroe (La.), and Columbus (Ga.). What's my next stop? Hint: ...
127 views

### How to think about permutation puzzles?

I know this is a very general question, but these kinds of puzzles are the only ones I can't figure out on my own. Rubik's cube, Twiddle, 16... (the last two are in Simon Tatham's Puzzle collection.) ...
176 views

### The entrapment of Beastly Gerbil

Part 1: The disappearance of Beastly Gerbil I've been trapped here for what feels like forever. This is all I've known. Darkness. The occasional flash of light, but then back to darkness, always, ...
540 views

### The disappearance of Beastly Gerbil

Part 2: The entrapment of Beastly Gerbil This is an unusual call in. As a private detective you have been asked to investigate several odd cases, but this you're still convinced this one is taking ...
113 views

### sequence made of <=> symbols

I tried to solve this sequence made of symbols: <=>, <=, >, <, ?, ?, => Here there's my reasoning: I thought this <=> as a full symbol and everytime the comma shifts to the ...
52 views

### k-threats Chinese Cannons Chess: Part 2

Inspired from the N-Queens problem, I here propose you a puzzle from Xiangqi wich is Chinese Chess equivalent, mostly played in Asia. The most different piece from Xiangqi is the cannon. You can ...
259 views

### Akari: Another Light

Rules (taken from Nikoli): Place light bulbs (circles) according to the following rules. Light bulbs may be placed in any of the white squares, the number in the square shows how many light ...
215 views

### Akari: The Light

Rules (taken from Nikoli): Place light bulbs (circles) according to the following rules. Light bulbs may be placed in any of the white squares, the number in the square shows how many light ...
106 views

### My whole ceases to be anything

My prefix isn’t affirmative My infix is somewhat a ring My postfix isn’t a prime My whole ceases to be anything
105 views

### Math Puzzle: Totaling up A,B, C [closed]

We know the following about the numbers $a$, $b$ and $c$: $$(a+b)^2=9,\quad(b+c)^2=25, \quad(a+c)^2=81$$ If $a + b + c ≥ 1$, determine the number of possible values for $a + b + c$
177 views

### 4-coloured queens attacking every opponent queen once

Can you place 6 queens from four different colours (24 in total), such that each queen attacks exactly one queen of each colour? They may attack as many queens of their own colour as these are ignored....
442 views

### Pieces of paper without consecutivity condition

TL;DR: like this puzzle but with an arbitrary number of papers and without the condition that the papers chosen must be consecutive. You are given $n$ pieces of paper, and you write down $n$ distinct ...
57 views

### k-threats Chinese Cannons Chess: Part 1

Inspired from the N-Queens problem, I here propose you a puzzle from Xiangqi wich is Chinese Chess equivalent, mostly played in Asia. The most different piece from Xiangqi is the cannon. You can ...
77 views

### Why did she choose O6G?

He gave her 8 choices. 7 lead to death, one lets her continue. O6A O6B I6C U6D I6E I6F O6G O6H Of course, he knew she had no idea. He turned the hour glass and gave her 5 items from his suitcase....
855 views

126 views

### Encrypted growing sequence

The following sequence has been encrypted: 1-0 3-0 6-1 ...
345 views

### A puzzle made special for today

Can you find the message hidden within this grid of puzzles?
190 views

### Where is this weird island?

Do you know me or do you know where exactly I am? I am an island in the atlantic ocean. Every day, people appear and disappear on me. I am invisible to humans but machines can recognize ...
373 views

### What city am I supposed to be travelling to next?

I'm currently on a trip around the United States (for pleasure) and am a little lost. I had it all planned out but lost my itinerary somewhere along the way. Thought maybe you could help. I started ...
132 views

### alphanumerical sequence,or symbols sequence

I've been challenged to solve this sequence, but I can not figure out the answer. I originally thought it was prime decomposition like: $96=2^5*3$ $12=2^2 *3$ $169=13^2$ But that reasoning only ...
210 views

### A descriptive cake

A 'geezer' walks into a bakery. The man is covered from top to bottom with tattoos - on his face, on his shoulders... even arrow tattoos on his fingers. He has dropped by to hand in a design for a ...
434 views
+50

### Shots, shots, shots, shots!

Once in a while I go out for a drink to my favourite bar. Normally is just drink a beer, eat some snacks and have a good time with my three friends. But last night I wanted to do some shots. The ...
92 views

### Complete the following analogical analogy

In an analogy ":" means "is to" and "::" means "as/like". Now, since this is almost an analogy (maybe a future type), I will accept the solution if it's almost correct. Kinberg : ‴niɘɈƨnɘƨiƎ‴  :: ?
355 views

### What is a Substantial 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 Substantial Word™. Use ...
I have in mind a special kind of die, one that is even more fair than uniform density dice. If the die has $n$ faces with labels going from $1$ through $n$, then some faces will be larger than others ...