# All Questions

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29 views

### Cube Connect Challenges

Cube Connect is a Flow-like mobile puzzle game on the surface of a cube. Rules of Flow (which is simply Numberlink with colors instead of numbers; copied from Nikoli rules with small modification): ...
42 views

### Most efficient way for people along the edges of a grid to move to the center

I'm considering an $2k\times 2k$ square grid ($k\in\mathbb Z^+$) with $8k$ highly rational people standing along the vertices forming the perimeter. All of these people want to go to the centre of the ...
38 views

### Cryptic Acrostic 1: Off Balance

This is an acrostic puzzle which uses cryptic clues. If you're unfamiliar with either or both of those, click the associated link. A complete answer should give the quote, author and source, as well ...
115 views

### Consecutive integers which have digital sums that are not relatively prime

What are ten smallest natural numbers n, such that n and n+1 have digital sums which are not relatively prime?
88 views

### Themed Boggle Grids

Inspired by this puzzle, I created (or discovered) these grids. Within each Boggle board is a set of words with a common theme. To make a word in Boggle, connect at least three letters horizontally, ...
93 views

### Fold the plane four times to get the maximum number of cross points

You have a straight line $l$ in an infinite plane. You can fold the plane along any straight line so the line $l$ becomes two rays with a common starting point. In the picture we fold along line $a_1$...
172 views

### A week around Europe

I've recently returned from a week of travelling around Europe, visiting a different town or city in a different country on each day, choosing my destinations according to an underlying pattern. I've ...
95 views

### A puzzling stained glass window

On a recent trip to Europe, I visited a beautiful gothic abbey. Walking up the dark aisle between old wooden pews, the air heavy with the odour of incense, I could only marvel at the beautiful stained ...
868 views

### Escape across the floorboards

A mad lexophile sits alone in his apartment obsessively rearranging his Scrabble tiles and writing words on every available surface, even filling each floorboard with a word. The Scrabble tiles have ...
234 views

### Math homework help

Thanks so much for helping me fix my grades in math, but I need your help again. I thought my homework would be easy. But then my teacher gave me some sample problems, and I don't understand them. ...
93 views

### Connection loss

hint: Find last word. bd be cd fh de HE fe lh pt mt bo* LE mk LA* pk ms PE* ve mt wd RG* * Changing things leads to the desired outcome. ...
124 views

### What are these words or phrases?

Given below are clues for 4 separate words or phrases. What are those? 1 Five letter word Having not intended 4 Go inside Leland No partial answers please.
587 views

### Tipping a tetrahedron in a plane

A regular tetrahedron with one black and three white faces is positioned with its black face at the bottom of a plane. The tetrahedron is tipped several times over an edge and finally reaches the same ...
76 views

### steganography riddle [closed]

I have this image of Lena in BMP format, which consist a secret message: And I got this hint for this riddle: My initial thought was going over the image row by row and get the LSB of pixels in ...
211 views

### Double Choco: I love myself

Rules of Double Choco: (copied from here) Divide the grid into regions by drawing along some of the dotted lines. Each region should have one group of gray cells and one group of white cells; both of ...
72 views

### What is happening tomorrow? [closed]

I posted this question on the Cross Validated stack exchange just now, but wanted to cross-post to here as well, because it is somewhat open-ended. A solution may be provided by myself or another ...
1k views

866 views

### How many "mathletic" couples were having dinner at the table?

Once, a number of couples, each one of them happening to be composed of a mathematician and an athlete (hence 'mathletic'), wanted, in order to diversify communication, to sit down at opposite sides ...
2k views

### The Facebook (a double connect wall)

This is a double connect wall puzzle. The objective is to rearrange the sixteen people below in the 4x4 grid such that each row of 4 will be related by a common theme and each column of 4 will also ...
1k views

### Nobody Likes This Rebus

The puzzle's answer is a single word.
81 views

### How can I find the shortest path solution or even begin to finding the most optimal solution to a weld robot sequencing problem? [closed]

Not sure this belongs here, but I thought I'd ask: How should I come to an understanding of an optimal weld sequence for a weld robot that welds a physical item on a revolving carousel (the gray T ...
201 views

### IQ test question - squares, triangles, dots

I have this question from a friend. We have no idea where to start. What is the correct answer and reasoning? Source: "Ghid de pregătire pentru concursul de directori/ directori adjuncți din ...
453 views

### Pipelink: A Cat for jkittykitkat

Rules of Pipelink: Draw a loop through the centers of all cells. Two perpendicular line segments may intersect (cross) each other, but not turn at their intersection or otherwise overlap. Clues show ...
176 views

### What number comes next in this evenly doubled sequence?

I've been playing around with sequences lately and found a pretty evenly doubled sequence of single digit numbers: 1, 12, 30, 64, 65, 156, 175, 368, 369, 371, 752, 753, 1524, 1525, 3060, 3073, 6168, ...
115 views

### An oddly formed sequence?

I've been playing around with sequences lately and came across one that was rather, odd. $101$, $123$, $147$, $189$, $191$, $213$, $217$, $279$, $...$ Hints Let $N_i = 101$... Can you determine the ...
56 views

### I need help figuring out this vigenere cipher [closed]

I got this from TheClineFamily who are running a contest on instagram Jpxppxmusxyqbsjqfjzmrnorvokoqvtftvpmqfwbqg The only clue I have to the key is this: March is my month. My time to shine. Don't ...
3k views

### I was popular in the 1970s

I was popular in the 1970s. I can be represented by the following image: What am I?
303 views

### Filling a grid with skinny trominoes which have arrows on their ends

Let's have a 10x10 square grid with 7 empty small squares. This grid is to be filled with skinny trominoes which have arrows at their ends (see figure 1). What is the maximum number of arrows which ...
302 views

### Spot that puzzle

This diagram solves an occasionally seen member of a well-known family of optimization puzzles.  Spots ● generalize a component that is represented variously in different statements of these puzzles. ...
678 views

### Hidden, concealed, imperceptible; What word is missing?

What word is missing? ...
165 views

### 4 steps with common theme

What are the 4 steps, what is their theme, and what is the result? ...
781 views

### Imagine a Sudoku with Text-Only: A Gridless 6x6 Antiknight Antidouble Sudoku

Imagine the following Sudoku: Imagine the Sudoku has a 6x6 grid with standard boxes, 2 rows and 3 columns each; and standard digits, 1 to 6. Imagine it has an antiknight rule: identical digits cannot ...
610 views

Across 1. Theatrical musical interrupted by a tram construction (12) 10. One-time Vatican resident's right to boycott Toyota vehicle (4) 12. Exhausted courier crammed small boxes (6) 13. Hong Kong ...
361 views

### Cipher "Jpxppx...": March is my month [closed]

The cipher is as follows: Jpxppxmusxyqbsjqfjzmrnorvokoqvtftvpmqfwbqgbvfxukntupcneul No spaces or anything.. and this is the hint: March is my month. My moment to shine. Don’t write about me or you’...
175 views

### As simple as 1,2,3?

What is the next number in the sequence? 1, 2, 4, 3, 9, 5, 6, 10, 16, 7, 11, 8, 25, 12, 17, 13, 14, 18, 36, 15, 26, 19, 20, 21, 49, 27, 22, 23, 28, 37, 24, 29, 64, 30, 31, 38, 32, 33, 50, 39, 81, 34, ...
1k views

### Who? What? Where?

WHO did WHAT, and WHERE? PHILIP CAUGHT A BIG C LY NADINE DEEMED TIRAMI WAY MATTHEW FELT THE TARM YAK PETE FRETTED A LOT ABOUT C EEK AGO QUINN HAD TO G HIONERS ERICA NOW HOME MISSED H NICALLY ...
365 views

### A dance between numbers

Given the following equation: $$\Delta = \Biggl(\frac{t \mod 6}{(t \mod r) + 1}\Biggr)^2$$ Find the relationship between $t$ and $r$, along with the properties of each, that ensures $\Delta = 9$. For ...
145 views

### An unusual subtraction

I saw this note jotted on a piece of paper on my friend's table. Jickpom 1–0 Ecarombhp ½–½ Khalerop 0–1 What did he mean by it?
2k views

### What comes next in this sequence? 2, 3, 1, 5, 7, …

Here's a sequence I can't solve. It includes every number from 1-14, does not include 15 and 16, and then has a 17. I think there may be a pattern in natural number progression but can't find it. What ...
250 views

### The Popup Annoyance

The story Fred, a software designer, woke up, got dressed, took a shower, ate breakfast, then headed off for work. He sat down on his chair and booted up his computer, only to see that all the files ...
265 views

### Egg drop problem for infinite floors

This is a modification of the infamous egg drop problem, which I have seen formulated as in the following manner: Given $e$ eggs and a building of $f$ floors, how can we find the lowest floor at ...
429 views

### Clash of the Robinsons

"Ridiculous!" you think "What can be the odds? Either I'm hallucinating or the amateur writing this story plunged to new depths of incompetence." Both being equally likely you don'...
393 views

### What a tangled web we weave

The answer is a relevant word.
231 views

### The maze of everlasting flowers

You were recently caught trespassing on the queen's hunting grounds. The punishment for this crime is a miserable experience the locals call the maze of everlasting flowers: The full resolution of ...
2k views

### Modification of 100 lightbulbs problem (everyone flips 100 bulbs each)

This is a modification to the usual 100 lightbulbs in a room puzzle. Like before, the first person flips the switch of every lightbulb. However, while the second person also starts from the first ...
344 views

### A number like waldo?

What is the smallest whole number that when its individual digits are summed, produces a number 4 digits long? For example, the number $5357$ is no where close since $5 + 3 + 5 + 7 = 20$. Note: I'm ...
295 views

### Circling the rectangle: A strange IQ problem

I'm sure you're all familiar with pattern recognition puzzles where you have to find the next picture in a sequence. Well, I’m completely stumped on this one… Can you help? There is a sequence of ...
193 views

### Please, I don't know greek!

data key result 7, 2, 17, 82, 56 0 ΛΞλν 1, 3, 8, 127, 65, 8 19 εΤψΒΖ 5, 64, 13, 9, 4, 42 7 δδιΡΠ 13, 9, 8, 657, 31, 3, 7, 5 3 ? Hints