# All Questions

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11 views

### Some luck involved

Can you guess the theme? Note: Rather easy if you have the knowledge, despite my efforts to toughen it up, so please no image search!
16 views

### Brain twisting maths sequence question

The answer is But what is the explanation?
66 views

### They all relate to one thing

1: $60$ $60$ $60$ 2: $\frac{n(n+1)(2n+1)}{6}$ 3: $\sqrt{s(s-a)(s-b)(s-c)}$ 4: $\frac{21}{7}$ 5: 25, 36, ? 6: $>90$ Find what all of these mean or what they represent (What I ...
88 views

### Find how many colors are needed to color all vertices

In this puzzle, you need to identify the minimum number of colors needed to color vertices such that no two adjacent vertices ...
86 views

### Found this on The Ohio State University campus on a pillar relatively hidden from view. Any leads? I’m clueless

Here is the photo of the code... I think. I don’t know what it could be, but it was duct taped to a pillar for several weeks before I was kicked off campus from COVID-19:
82 views

### NineFind - Which 9 Numbers Are Correct?

Text Version: ...
57 views

### Need help for a sto-stone puzzle [closed]

I need help for this puzzle. The name is Sto-Stone, a friend sent me for geocaching.
248 views

### Place the numbers 1-7 in the squares so that each row and columns adds up to the same total

A F B D E C G A+B+C = B+D+E = F+E+G Numbers 1,2,3,4,5,6,7
149 views

### A short puzzle especially for social isolation time

Solve the following analogy. ":" means "is to" and "::" means "as". Text only:
190 views

### 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 (...
269 views

### Analogy with Number

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

### Elementary, my dear Louis

Felt it was time for another Density™ puzzle. Warning: May require thinking. Enjoy! Final answer: (3,4,4,4)
114 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 :
1k 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 ?
76 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 a hat. Hint
627 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 ...
260 views

### Number Guessing (Part 1)

I thought up two positive integers 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. ...
155 views

### That letter sequence started so nicely

Find out how the following letter-sequence is constructed: ...
236 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, ...
124 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 ...
351 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 (•) = ...
290 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 ...
112 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
125 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 ...
195 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 ...
216 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 ...
101 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 ...
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 ...
58 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 ...
109 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 $a + b + c$
81 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....
95 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‴  :: ?
204 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 ...
354 views

### A puzzle made special for today

Can you find the message hidden within this grid of puzzles?
134 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 ...
222 views

### Usually in games!

Try to replace the question mark with the help of the clue! The clue will make you understand what those symbols represent. Now you just have to find the pattern! (The vertical bars are just there to ...
864 views

188 views

### 9 (plus or minus various things) is the opposite of 8

Find a word, whose pattern is such that is fits the nine letters as follows. Then change it accordingly so that its pattern becomes eight letters as follows respectively. ...
106 views

### The bus again, or is it a pen?

This image can be resolved to a single word. What am I? Images were taken from https://icons8.com/.
180 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....
105 views

### Venetians attracted to Mary Jane

Across 1/5. Trouble with battle making a neighbourhood essentially warmer (3,5,6) 10. (See 14 down) 11. Place with obstructed view to Venetians, perhaps attracted to Mary Jane (5,4) 12. Activity to ...
223 views

### Nurikabe minicubes: the Boondoggle, the Lollygag, the Dillydally

These are three-dimensional Nurikabe puzzles. In each case, the four squares represent the layers of a $4\times4\times4$ cube. The goal is to shade some cells in each layer so that the resulting space ...
346 views

### An extremely fair die

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 ...
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 ...
128 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.) ...
117 views

### Technology island

Here is a very easy riddle for you: I am a piece of land but I am also technology. I am drowning and many people think that my time is over. But still, many people build on me. Some people ...
451 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 ...
232 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 ...