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What is “A non-PC American woman overseas?”

I'm stuck on the last clue of a cryptic crossword. The clue is: A non-PC American woman overseas? (6) The cross letters are A_R_A_, confirmed by "check answers." Cryptic Crosswords iPhone app, ...
264 views

Is there any specific way to play Solitaire?

I am interested in finding out if there is any specific way (algorithm) to play solitaire (not the card game)
417 views

Mean to confine flower that's fibrous (7)

From the Guardian Cryptic crossword No 26,271, set by Chifonie: Mean to confine flower that's fibrous (7) The confirmed answer is I can see the definition, and I think part of the wordplay, but ...
9k views

Aside from brute force, how can I solve this puzzle?

Once upon a time, and old lady went to sell her vast quantity of eggs at the local market. When asked how many she had, she replied: Son, I can't count past 100 but I know that: If you ...
222 views

What are the odds that there is no solution on a given Set board?

I was playing a game of Set with a group. We had the usual twelve cards out and all agreed that there was no set. We then increased the number of cards to fifteen and were still unable to find a set....
2k views

How to solve Oskar van Deventer's gear maze 2x2

One of Oskar van Deventer's puzzles is the gear maze 2x2.There are 4 gears connected together so if you move one gear all four gears rotate (two clockwise, the other two counter-clockwise).On the ...
979 views

Are there any puzzle/solitaire games based on chess?

First, I apologise for asking a question that's not strictly in the right Q&A format; I'm hoping there are quality answers anyway. Are there any puzzle or solitaire games based on chess? By this ...
6k views

Is there an algorithm for the Rubik's 360?

Is there an algorithm to help me solve the Rubik's 360? Usually I just do it at random, but I rarely succeed.
1k views

Are there any popular puzzles with polynomial-time algorithms?

First, a little background: as I noted in my answer to another question here, most of the puzzles that seem to stay popular for extended periods of time are canonically 'hard' in an algorithmic sense: ...
1k views

How many digits can be removed from a multiplication puzzle and still give only one answer?

There's a common category of mathematical puzzle which involves determining missing numbers in a long multiplication problem. As an example from this site (problem 10): ...
4k views

How many squares can 4 queens control?

Though there is no strict mathematical proof, it has been shown via brute-force that no arrangement of 4 or fewer queens can control every square on a standard 8x8 chessboard. So, out of the 64 ...
686 views

What size of puzzle is appropriate?

I am making a puzzle based on a Project Euler problem. Here is the puzzle at present: What path in the triangle below, starting from the top number with each step moving to one adjacent number in ...
22k views

Why does this solution guarantee that the prince knocks on the right door to find the princess?

I found this puzzle online: On the top floor of a castle lives a princess. The floor has 17 bedrooms arranged in a row. Each bedroom has doors connecting to the adjoining bedrooms as well as to the ...
1k views

What kind of glues are not conducive to long-term puzzle preservation?

If one has a very large puzzle of an image that one desires to mount and frame; what kind of glues would damage the puzzle piece over time? I have heard of 'puzzle glues', but question if this is ...
1k views

How Random does a 3x3x3 (or other rubik cubes) need to be in speed solving?

Is there a rule/method to know how "random" should the cube be when solving it? in order for it to be a "valid" score?
2k views

What is the Rush Hour puzzle with the most steps in its solution?

Rush Hour is a well-known sliding-block puzzle in which you push cars around (each car moves horizontally or vertically) to let a red car escape the grid. The standard board is a 6x6 grid, with four ...
518 views

What are the conventions telegraphing when answers are abbreviated in New York Times crosswords?

There are a number of conventions you can count on fairly consistently in the New York Times crossword. One is that abbreviated answers are "signaled" somehow - an answer that is an acronym/...
2k views

Why is “trapeze” the solution to this cryptic crossword clue?

I was doing a cryptic crossword this morning and I came across the following clue: Circus equipment has chimpanzee, say at the centre The answer is "TRAPEZE" (confirmed by "check answers"). The ...
871 views

How do people decide which words to use in crossword puzzles?

I've tried my hand at creating a crossword a few times, but generally there have been way too many interlinks between words for me to create even a solution grid with any ease. Often I get about a ...
22k views

Is it possible to scramble a Rubik's cube such that no two squares of the same color are touching?

My friend always insists on scrambling my Rubik's cube "perfectly" before giving it to me to solve. According to his definition, a "perfect" scramble must have no three of the same color touching (...
2k views

If I want to create word search puzzles what approach is best?

It seems like most word search puzzles have a quantity of words that match some theme, arranged haphazardly, with some random letters filling in the extra spaces. If I want to create word search ...
20k views

Where should I start on the Ghost Cube?

The Ghost Cube is a 3x3 shape modification which is solved when two layers are rotated out of position. As a result, in order to solve the puzzles, you need to move pieces into positions where they ...
912 views

A building with an odd elevator

In a building, there is an odd elevator, which has only two buttons: UP, which makes it go up 9 floors, and DOWN, which makes it go down 7 floors. (The ground floor is floor 0.) It is possible to ...
3k views

How do I solve the C4Y 3x3x7?

I have been solving the Rubik's Cube 2x2x2, 3x3x3, 4x4x4 and 5x5x5, and because things are very similar I thought a 6x6x6 wouldn't be a challenge much. So I bought the C4U 3x3x7 - see image. What I ...
2k views

4x4x4 Rubiks Cube strategy

With a 4x4x4 cube, it's possible to apply the same strategies as for a 3x3x3, either treating it as a 3x3x3 with a double-width middle or else as a 2x2x2 and just working on the corner "quadrants". ...
9k views

How do you solve a word puzzle when you have no idea where to start?

When you're looking at a logical word puzzle, what sorts of clues should you try to look for to solve them? There have been quite a few puzzles posted to this site so far that I spent a few minutes ...
3k views

Winning an unfair game

I came across the following interesting problem today: A game consists of a sequence of plays; on each play either you or your opponent scores a point, you with probability 𝑝 < 1/2, he with ...
424 views

What is the solution to the generic round table problem?

This question was asked about a group of people whom a king wishes to play a cruel game with. Going around in a circle, the king kills every other person. The question concerned how one could ...
2k views

You are a cat. How do you swap?

Number twenty-one cages containing mice, 1, 2, 3, etc., up to 21, and place them in the following order: 1 14 15 17 3 7 13 6 20 2 19 21 5 18 8 11 16 9 12 4 10 ...
3k views

What is the lowest you can get in 2048? [duplicate]

What is the lowest score you can get in 2048? Creating high numbers is obviously bad, but what about not matching numbers? What is the chance of getting this lowest score?
7k views

Variation of 100 prisoners light problem

There is a classic problem below for which Dr. Yisong Song wrote a very well written and thought out series of solutions. The variation here I've never seen anywhere but am curious. I want to work it ...
4k views

Differentiate between the numbers from 1 to 5 with one single yes/no question

This question requires a bit of logical distortion to get the information required to answer the question. However, I've never seen it asked before what would happen if more modes of question ...
6k views

N pirates steal their share of bananas to the benefit of a monkey

The following is a type of logic / math puzzle I've yet to see on this site. I feel it belongs because the kernel of this problem can be reworked into other puzzles. $N$ pirates find themselves ...
4k views

How do you solve the circular table problem?

One classic puzzle has many different forms, but the basic strategy is the same. Once upon a time there was a crazy king who had a very wise minister with him. The king had a habit of playing a ...
4k views

Is it indeed impossible to score any points in the test in Heinlein's “Space Cadet”?

In Heinlein's Space Cadet, one of many tests administered to the protagonist seems to have no way of scoring any points. See the excerpt below. Late in the day he was ushered into a cubbyhole ...
865 views

Clock Puzzle problem

Today I came across this puzzle: How many minutes is it until six o'clock if fifty minutes ago it was four times as many minutes past three o'clock? Any help?
17k views

How do I approach a “stuck” game of minesweeper?

I've played many a-game of minesweeper, and I frequently reach positions in which there is no logical, deterministic way to come to a conclusion about how I should solve the puzzle. How should I ...
19k views

What is the optimal starting strategy in Minesweeper?

Is it better to start in a corner, edge, or any random middle square? If the first square isn't empty, when is it better to click a neighbor vs. another random square? How does the strategy vary by ...
20k views

What frequent patterns can be used to overcome Minesweeper obstacles?

Minesweeper, to those who do not know the strategies involved, is a difficult game. What patterns exist in the game which I can take advantage of? Meta-context: this question is an offshoot of ...
3k views

Is it always safe to click first in the lower lefthand corner of a Minesweeper puzzle?

I always start a Minesweeper puzzle in Windows by clicking the cell in the lower left corner. Even though I have never seen a bomb there, how sound is this strategy? Is it possible that some time in ...
1k views

How could I have avoided this mistake in Minesweeper?

The puzzle grid pictured below is a prime example of the classic rush to judgment: I was so sure of my decision, but when I double-clicked to clear more cells, the cell to the left of the one I had ...
6k views

Are there any forms of patience or solitaire that can be solved by logic alone?

Single player games using a single deck of playing cards often called patience or solitaire, generally involve a degree of skill and luck to solve, with card shuffling ultimately being the deciding ...
2k views

When and where was the first logic-grid-based puzzle published?

Logic puzzles with a set of conditions and a "logic grid" are very popular. More than one publisher is currently producing puzzle books with these types of puzzles. A Wikipedia article claims ...
480 views

In the three-card monte, can a logical principle be applied to increase the odds?

Assuming the game is played without cheating, in the three-card monte, can a logical approach increase the player's chance of beating the house? At first glance it would seem to be unlikely but a ...
484 views

How to deal with conjugate-pair pseudocycles when solving Sudoku

In single-solution regular Sudoku puzzles, sometimes you may encounter a combination of possible cell solutions such as: {2,7} in A1 and A7 (same row) {2,7} in A7 and B8 (same box) {2,7} in B8 and E8 ...
219k views

What is the best method of scrambling a rubik's cube?

If I wanted to solve a physical Rubik's cube multiple times, for practice, what is the best, most random way, to scramble the solved cube? The best way I can think is to hold it behind my back and ...
18k views

You have one question to tell whether the number I'm thinking of is 1, 2, or 3

This is an interesting puzzle which was passed to me by a friend some time ago. I do know the answer, but will refrain from self-answering on this to see where it goes. I'm thinking of a number: 1, 2,...
3k views

What is the maximum number of empty 3x3 blocks a proper Sudoku can have?

It is possible to have a proper Sudoku with one empty block (consisting of 3x3 cells). The trivial (and very boring) example would be a puzzle where all other cells are given. It's impossible to have ...