Questions tagged [logical-deduction]
A puzzle that requires formal logical deduction to arrive at the solution. This suggests more than merely reasoning through clues to find an answer (you might want [situation] for that).
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PSE Advent Calendar 2023 (Day 9): The Peppermint Twist
This puzzle is part of the Puzzling Stack Exchange Advent Calendar 2023. The accepted answer to this question will be awarded a bounty worth 50 reputation.< Previous Door Next Door >
This puzzle ...
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PSE Advent Calendar 2023 (Day 11): Divide the cookies and milk
This puzzle is part of the Puzzling Stack Exchange Advent Calendar 2023. The accepted answer to this question will be awarded a bounty worth 50 reputation.< Previous Door Next Door >
Santa’s ...
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Quadritaisho: The sports bet
My friend from America was going to watch a game and wanted to bet I couldn't guess where he was going. The answer lies in the Quadritaisho puzzle below. Can you help me find out where he's going to ...
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What should be in box 4?
Box 1: April, June, September, November.
Box 2: March.
Box 3: January, May, July, August, December.
What should be in box 4, and why?
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Another type of Sudoku puzzle
I just found a weird-looking sudoku I left years ago in my basement:
I think there was a specific name for this type of puzzle, but I forgot to write it down and now I can't remember it!
The only ...
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Turn Back the Clocks
This is part 45 of the puzzle series Around the World in Many Days. Each part is solvable on its own.
Dear Puzzling,
This is a Slitherlink puzzle. Draw a single continuous loop along grid lines that ...
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Filling in an 8x8 minesweeper grid with mines (Day 11: Christmas tree edition)
Previous puzzles
Contains: Single mines (1 mine), Double mines (2 mines), Triple mines (3 mines)
To get the $\color{green}✓$:
Solve the Nonogram
Solve the Minesweeper puzzle
Note: partial answers ...
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Fill this 5x5 number grid incrementally, either by moving two boxes diagonally or moving three boxes in a row or column
One day, a friend has shown me a 5 by 5 grid, challenging me to fill it with numbers from 1 to 25.
Obviously, it is not simple because there are some rules:
The number 1 is placed in the center of ...
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What technique can be used to solve this 6x6 sudoku?
Which Sudoku technique can be used to solve this? The screenshot is from the open source Sudoku app by SECUSO (Security Usability Society) for the Android platform.
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PSE Advent Calendar 2023 (Day 3): 24 dangerous doors
This puzzle is part of the Puzzling Stack Exchange Advent Calendar 2023. The accepted answer to this question will be awarded a bounty worth 50 reputation.< Previous Door Next Door >
Task: Solve ...
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Multi smol boi puzzle I: apologies
Disclaimer: Jryy, svefg bs nyy, V jbhyq yvxr gb ncbybtvmr. Abg sbe npgvbaf (jryy bxnl, sbe npgvbaf), ohg sbe zl fzby obv pvcure. Vg frrzf gung zl svefg fzby obv chmmyr jnf whfg n ovg gbb uneq. Fb, gb ...
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160 foxes are stuck on an island with 1 chicken. Will the chicken be eaten? [duplicate]
An island is filled with apple trees and other plants. The only inhabitants are 160 foxes and 1 chicken.
The foxes are smart, logical, and completely aware of their surroundings. They have two food ...
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What is the next logical step I can take when solving the Nov. 30 2023 Sudoku in the Wisconsin State Journal?
Note: sorry for posting this on Dec. 1, but don't worry, I haven't looked at the Sudoku solution yet.
So today I decided to try to solve the Sudoku in the Wisconsin State Journal. Now, even though ...
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Is the "Challenging" Kenken in the Wisconsin State Journal from April 27 2021 solvable?
Note: The reason that I picked this one to self-answer was because it was a few weeks (months?) before the Wisconsin State Journal stopped printing Kenken puzzles. This was also the newest Kenken from ...
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Filling in an 8x8 minesweeper grid with mines (Day 10: Double Neighbors)
Previous Minesweeper puzzles
Based off of Day 10 of the Minesweeper Advent Calendar on heptaveegesimal.com
Difficulty (approximate): ★★★★☆
Contains: Single mines (1 mine), Anti-mines (-1 mines), ...
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Sudoku variants #2: Lined Numbers (6x6 grid)
Previous variant
Today's Sudoku variant is a bit weird. Here's why:
Take this screenshot:
From this, you might argue that there is nothing that can be logically deduced on this grid. Now you might ...
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Relatively prime numbers
Can you fill in the circles with numbers such that:
Each pair of circles connected by one line contains relatively prime numbers
Each pair of circles connected by two lines do not contain relatively ...
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Another puzzle combination (feat. Kakuro)
Today, I am going to give you another puzzle combination. This time, it features a Kakuro! However, there are some things to note:
There are only two puzzles that I have combined, although you have ...
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Equality-breaking function
There's a function that satisfies the following:
$f(2) = 1, f(2^2) = 2, f(-3^3) = 3$
$f^n(x) = 3(n-1) + f(x)$
Where $f^n$ means $f$ composed with itself $n$ times.
Lastly, $f$ is not equality ...
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Filling in an 8x8 minesweeper grid with mines (Day 8: Not a single mine)
Difficulty (approximate): ★★★☆☆
Contains: Double mine, triple mine
Now you might be wondering: If this puzzle contains not a single mine, then why does it contain mines? Well, that's because there ...
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A Hokuro, but with a twist!
Recently, I created my first Hokuro puzzle, which was received really well. However, this time, there is a twist! Not with the rules or anything, however, it is combined with a Nonogram! Luckily, the ...
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A 6x6 table with nothing filled out?
So as you might or might not know, I can be quite evil sometimes, especially with my Hidato puzzles that contain no numbers.
But, today, I decided to give you an enigmatic-puzzle! This means that you ...
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Press The Grue Button
[This puzzle is inspired by the webpage https://apparenthorizons.com/2017/10/12/the-grue-problem-and-deep-learning/]
55 workers have got a chance to double their pay, as said by their boss. So, the ...
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Anyone up for a 3x3x3 Hidato?
So, I have been pretty evil with how I make Hidato puzzles lately, with there being no numbers. To make up for it, I have decided to make a 3x3x3 Hidato for you all. Yes you read that right. I made a ...
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Cattell IQ Test
Some of Cattell IQ Tests really stuck me. So I hope you can help me.
In these two tests, which one is true according to the logic?
And in this one, we find two odd pictures, probably some kind of ...
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How would I be able to solve this difficult Hidato?
So I was doing Hidato puzzles on the official Hidato site when I came across this puzzle that I am having trouble solving, and while I have been able to solve it partly, I don't think that I'm going ...
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Minimum Races for Top 3 horses
There are 37 horses and 6 horses can race each time on a track. Find the fewest number of races required to get the top 3 fastest horses.
Source - Glassdoor
I know we can definitely do it in 9 races ...
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A Hidato, but with no given numbers? #2: 5x5
Previous puzzle
As you may or may not know, I can be a bit evil sometimes. Today, I am going to give you a 5x5 Hidato with no given numbers to start. However, this isn't a Mobius Strip puzzle like ...
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The puzzle of the day
This is called Hidato or Snake Puzzle !
The goal of Hidato is to fill the grid with consecutive numbers that connect horizontally, vertically, or diagonally. For your help, the grid is already filled ...
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A question from Bob to Bob
Set-up:
John and Bob are playing a game that goes like this:
Bob is alone in a completely opaque, featureless room.
Bob chooses a question, though some types of questions are off-limits, which will ...
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A Hidato, but with no given numbers?
I can be a bit evil sometimes. Today, I am going to give you a Hidato with no numbers! It gets worse: This puzzle is on a Mobius Strip Y[1] However, I will give hints as to what the numbers are, so ...
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Feedback on a themed Nonogram/Hidato puzzle combo with a cell color gimmick
So, as you might know, the Christmas season is coming up. (17 days until Dec. 1 at the time of writing)
I'm thinking of posting some Christmas-themed puzzles during that season, and just want some ...
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A Hidato, but with a complex twist!
Today's Hidato puzzle has a pretty complex twist. What is the twist, you ask?
This is what the twist is:
There are three different colors:
Yellow: Represents a prime number
Green: Represents a ...
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Double Choco: Snaking
Rules of Double Choco:
Divide the grid into rooms along grid lines.
Each room contains two halves: one orthogonally connected area of shaded cells and one orthogonally connected area of unshaded ...
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My first puzzle combination: A Nonogram and Hidato
Today's puzzle is a bit strange. Why, you might ask? Because it is a Nonogram and a Hidato combined!
Rules of Nonogram:
The grid must be colored or left blank according to numbers at the side of the ...
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A Trivial Pursuit #12 (Sports and Leisure 2/4): Logic Boat
This is part 12 of A Trivial Pursuit, a 25-part puzzle hunt. Each part is solvable on its own, with the exception of the meta-puzzle at the end.
This is a variation on a Battleships puzzle, where the ...
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A Trivial Pursuit #25: Meta-Analysis
This is the final part of A Trivial Pursuit, a 25-part puzzle hunt.
Having solved the previous 24 sub-puzzles in this series, you have managed to find 24 keywords that will help you extract the ...
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A (maybe) simple Hokuro puzzle
Hokuro is a puzzle that was introduced to the Puzzling Stack Exchange on December 2nd, 2020 by sarsapilla as an entry for Fortnightly Topic Challenge #44: Introduce a new grid deduction genre to the ...
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Hokuro Puzzle: Introduction
This is an entry for Fortnightly Topic Challenge #44: Introduce a new grid deduction genre to the community.
This puzzle type is inspired by Kakuro, and it has similar rules.
Kakuro is short for '...
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A fun and simple Nonogram... ...with a cipher
Goal of this puzzle: Find the hidden message in this Nonogram that I created.
The puzzle:
play online
Hint:
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Knights and knaves variations
The knights and knaves puzzle is old, well known and thoroughly solved.
https://en.m.wikipedia.org/wiki/Knights_and_Knaves
In Labyrinth there's a variation, where one of the participants tell us the ...
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Touching Base (Checkered Fillomino)
This is a Checkered Fillomino puzzle, with the following rules (adapted from the linked page):
All numbers on the grid must be part of a polyomino of the same value.
No two polyominoes of the same ...
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12 logicians each have a number written on their foreheads
12 logicians each have a number written on their foreheads, visible to all but themself. One day, a meta-logician comes by and remarks, "I see all the numbers are distinct natural numbers." ...
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Sudoku variants #1: Schrödinger's Grave (6x6 grid)
Not in conjunction with my Minesweeper puzzles - that would be concerning!
Inspired by Cracking The Cryptic's video "The Graveyard Of Schrödinger" (original gimmick by fjam)
How this ...
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What are the hidden digits in this long division puzzle?
The following problem was given in the Eureka journal (April 1978/University of Cambridge). This problem can be solved by hand without computers. There is a unique solution. The phrase, "exact ...
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How do I determine whether a 5x5 Lights-Out puzzle is solvable without trying to solve it?
The following two 5x5 Lights-Out puzzles are not solvable. Is there a way to find out why, without trying to solve them?
[1, 0, 0, 1, 0]
[1, 1, 1, 1, 0]
[1, 1, 1, 0, 0]
[0, 0, 1, 0, 0]
[1, ...
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A 4x4 sudoku shouldn't be that hard, right? Right?
Note: this is not in conjunction with my Minesweeper puzzles
Got this idea from one of Cracking the Cryptic's videos, I don't remember which one though. This exact puzzle is still overall unique.
...
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A 10x9 Hidato puzzle with a cipher
rot18(A se zgfwkldq jwsddq tsv sl ujwslafy hmrrdwk kg zghwxmddq sl kgew hgafl A sulmsddq kzgo aehjgnwewfl dgd)
You might note that something is off about the following Hidato puzzle. Well, I guess in ...
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Filling in an 8x8 minesweeper grid with mines (Day 9: Complex mines)
Contains: Complex mines ($i$ mines, where $i:=\sqrt{-1}$), Anti mines (-1 mines)
Note: This is in conjunction with my Minesweeper puzzles
Sorry for not posting a Minesweeper puzzle yesterday. I will ...
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An introduction to Hidato (also known as Hidoku)
Note: this is not in conjunction with my Minesweeper puzzles
In all honesty, I don't know why I decided to look up this type of puzzle since I also have never heard about it, and there doesn't appear ...
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