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).

Filter by
Sorted by
Tagged with
3
votes
2answers
30 views

Heyacrazy: Careening

This is a Heyacrazy puzzle, designed at request of testsolvers of previous puzzles who wanted to see how longer diagonals would work. Rules of Heyacrazy: Shade some cells of the grid. Shaded ...
10
votes
2answers
427 views

Slitherlink Fillomino hybrid

This puzzle is a combination between a Slitherlink and a Fillomino. You should put a number in each square and draw a single closed loop over the grid such that the following properties are satisfied:...
7
votes
2answers
876 views

Earth rotation discrepancy

Some time ago, I discovered that planet earth's sidereal rotation period equals 23 hours, 56 minutes, and 4.1 seconds (see for example this Wikipedia article). The sidereal rotation is the rotation of ...
6
votes
2answers
132 views

Heyacrazy: “LMI”

This is a Heyacrazy puzzle, originally constructed for a test for Logic Masters India. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded ...
6
votes
1answer
121 views

Heyacrazy: Forks

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is ...
9
votes
1answer
313 views

Heyacrazy: Crosses

This is a Heyacrazy puzzle. Heyacrazy is an original genre, inspired by the "two border" rule of Heyawake and Heyawacky. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot ...
-4
votes
0answers
126 views

Real Life Chaos Theory Puzzle [on hold]

I accidentally threw a red at my teammate during a Mario Kart Wii organized race, causing someone else to be banned from a MKW lounge for a week as a result. Try to figure out the missing steps. If ...
14
votes
2answers
385 views

Heyawacky: Ace of Cups

This is a Heyawacky puzzle. The rules are the same as Heyawake, but non-rectangular regions are allowed. Rules of Heyawake: Shade some cells of the grid. Shaded cells cannot be orthogonally ...
6
votes
0answers
392 views

Dodgy Dies: The Puzzling Premiere

Inspired by the "Treasure Hunter Monolith" minigame from Danganronpa V3 Dodgy Dies Guide Terminology Block - a single die on the grid. Cycle - a list of blocks Value - the ...
19
votes
2answers
1k views

Heyawake: An Introductory Puzzle

This is a Heyawake ("divided rooms") puzzle. Rules of Heyawake: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. ...
3
votes
1answer
160 views

Missing Number in a Seven Segment Circle

What number should replace the question mark? Please be helpful. If you have the answer, please reply to this post with the explanation and answer. If you don't have the answer, then don't comment. ...
-4
votes
1answer
148 views

A riddle from Candy Cadet [closed]

I am Candy Cadet, come get your candy here. I have candy all day, everyday. Candy. Candy. Candy. Now I will tell you a story about a young woman who was sealed in a small room. In the room was a ...
1
vote
1answer
78 views

Seed is to sprout as [closed]

I came across this question and couldn’t find an answer to it. The question goes like so: Seed is to sprout as A. Plant is to grow B. Garden is to weed C. Dawn is to morning D. Teenager is to ...
16
votes
1answer
360 views

Statue Park: Apollo 11

This is a Statue Park puzzle, made in honor of the 50th anniversary of the Apollo 11 mission. Rules of Statue Park: Shade some cells of the grid to form the given set of pieces. Pieces may be ...
11
votes
2answers
3k views

The grades of the students in a class

You are a new Math 102 professor in a university class of 88 students and would like to learn their grades from previous semester to know your students better and put a note of it to get an idea how ...
17
votes
5answers
3k views

Help me, I hate squares!

There is $5$x$5$ equidistance matrix dot given as below; You need to remove dots from the figure where it will be impossible to form a square by drawing lines between dots at the end. So what is ...
6
votes
5answers
863 views

Violations of the law

I live in A but work at B. The two are 45 minutes apart and I could commute back and forth either by driving or by taking the bus. Every day, before going from A to B in the morning and before going ...
8
votes
1answer
166 views

Yajisan-Kazusan: Diagonal Arrows

This is a Yajisan-Kazusan puzzle. Rules of Yajisan-Kazusan: Several numbered arrows are given in the grid. Shade some cells so that: no two shaded cells are adjacent unshaded cells form ...
10
votes
3answers
304 views

Black to play and win (Teeko)

$$\def\S#1{\phantom{\Space{18px}{22px}{0px}}\llap{#1}} \begin{array}{|c|c|c|c|c|}\hline \S{}&\S{}&\S{}&\S{}&\S{}\\\hline \S{}&&&&\\\hline \S{}&&X&O&X\\\...
12
votes
1answer
222 views

Masyu-making game

Two players are playing a game on a $4\times4$ board. The players take turns adding either a white circle or a black circle into any empty square, so that the board makes a solvable masyu puzzle (with ...
3
votes
2answers
234 views

5 Precommitting Pirates Puzzle

Another variant of the Pirate Puzzle, inspired by this variant and a bit more complex. Scenario: Five pirates of different ages obtain 100 gold pieces in total, and want to decide how to split them. ...
-3
votes
1answer
183 views

we are five we have three thousand four hundred fifty who are we? [closed]

we are five we three thousand four hundred fifty, who are we ?. Its a riddle like question but stranded with getting the answer for this question , am very sure the answer will make me slap my head ...
5
votes
2answers
134 views

3D Nonogram - Spinoff of the Reboot

This puzzle is inspired by recent 3D nonogram puzzles by Jafe and Omega Krypton. Check those out if you want, but they are not required to understand this puzzle. This 3D nonogram has clues with two ...
5
votes
1answer
273 views

5 Negotiating Pirates Puzzle

5 pirates of different ages have a treasure of 100 gold coins. On their ship, they decide to split the coins using this scheme: The oldest pirate proposes how to share the coins, and ALL pirates (...
7
votes
2answers
260 views

Nono-cube - Ultimate Puzzle Giant

Prologue - Instructions Shamelessly copied and pasted the following from @jafe's puzzle :P This is a three-dimensional nonogram. The first square gives the enumerations for the Z-axis, top to ...
2
votes
2answers
243 views

Minimize sum of guesses to win lottery

Ten boxes are given with $a_1,a_2,a_3,a_4,a_5 ......a_{10}$ number of balls in them respectively .These boxes are randomly ordered but $a_1,a_2 .....a_{10}$ is told.We can arbitrary select a box and ...
2
votes
0answers
114 views

What should be the missing number? [closed]

What would be the missing number?
2
votes
1answer
201 views

The chariot race

In a chariot race only 4 cars came to the finish: the blue, the green, the red and the white one. Titus, who is in bed with a cold, inquires to Quintus about the outcome of the race, because he ...
2
votes
1answer
127 views

Oops! Mixed up Multiplication - Needs to be Fixed

$Given$: $U$, $V$, $C$ are distinct digits, varying from 1 to 9. $U$ > $V$ > $C$ $UVC$, $VCU$, $CUV$ are concatenated Numbers $(UVC)*(VCU)*(CUV)$ = $234235286$ The digits on the right hand side ...
5
votes
1answer
263 views

pattern recognition riddle

does anybody see in this pattern recognition riddle a reasonable solution? source: https://www.physicsforums.com/threads/visual-pattern-recognition-test.921583/
11
votes
1answer
1k views

The three greedy pirates

Her eyes lit up as the pirates Sparrow, Barbossa and Turner opened the treasure chest and saw the mountain gold coins. After pirate's tradition, Sparrow first took a coin, then Barbossa two, ...
12
votes
4answers
4k views

The joke office

Alice and Bob are supposed to get form A at the joke office. Forms A, B, C, D and E are each at exactly one of the following five terminals. At one Terminal is only one form. Terminal 1: Here ...
8
votes
2answers
740 views

IX-NAY on the IX-SAY

Will this sequence ever have a 6 in it? 9, 1, 1, 1, 10, 3, 1, 1, 10, 5, 1, 1, 10, 1, 5, 2, 1, 1, 10, 1, 1, 1, 5, 4, 1, 1, 10, 3, 1, 1, 5, 1, 1, 1, 5, 2, 1, 1, 10, 5, 1, 1, 5, 3, 1, 1, 5, 4, 1, ... ...
2
votes
1answer
115 views

What is the Last Digit in the Result of the given Expression? [closed]

$Given$: $ASC$ is a concatenated number with distinct digits. $S$ is square of $A$, $C$ is cube of $A$ Deduce the last digit of the following Expression through Deductive Reasoning only: $$\begin{...
1
vote
1answer
51 views

Pan Digital Split among Two Powers

$Given$: $AB$, $DBCE$,$AGFPQR$ are three concatenated numbers with all distinct digits varying from zero to nine. $AB^C$ = $DBCE$ $AB^F$ = $AGFPQR$ Deduce all the digits through logical reasoning ...
0
votes
0answers
87 views

IQ test question help [duplicate]

Can you help me with the solution of the matrix? It has been asked before here 2 but a valid and well explained answer was not provided. Source without answer: here
12
votes
4answers
499 views

Red and White Squares

There are two grid boards with the dimension of 9x9 and 14x14, consist of all white squares. You are supposed to color some squares with a red color on the conditions below: In a board, if two square ...
-5
votes
1answer
102 views

Fibonacci again..Distinct Digits..Detail all your Deductive Steps [closed]

$ABB$ $CDE$ $GFB$ $DPGB$ $QPFR$ $RDFD$
3
votes
5answers
2k views

Explain how 'Sharing the burden' puzzle from Professor Layton and the Miracle Mask should be solved

Two porters have to carry six pieces of luggage of unknown weight. Each piece weighs a different amount, and they are labeled in order of weight from A to F, with A being the lightest and F the ...
2
votes
1answer
115 views

Deduce Distinct Digits of the Given Fibonacci Sequence- Detail all Steps

$DEPUS$ $SRST$ $UDQD$ $CTQU$ $DTPR$ $PQR$ $SDE$ $VRR$ $CVV$ $DUU$ $QP$ $TT$
3
votes
1answer
164 views

Valiant Knight is back..but he is in grave danger from the Evil Queen

King has placed a bounty on Valiant Knight and enlisted his evil queen’s help. Queen knows knight’s regular stops of his journey and knows he goes through all odd prime cells. She strategically ...
0
votes
1answer
76 views

How do you make Prime “COMPUTERS”?

$Given$: $COMPUTERS$ is the smallest Pan Digital containing all the digits 1 to 9 occurring only once. $COMPUTERSV$ is a Prime only when one of the correct digit ($V$)is added at the end. Also, $...
14
votes
2answers
704 views

The alcoholic village festival

The villages Arriba and Abajo together have 2019 inhabitants. At the annual festival are more than 2000 villagers this year. When they form a huge circle for dancing, everyone calls happy: ...
7
votes
2answers
239 views

Listen to my Story…Let us find the Unique Invisible Pan Digital Pair

I was an avid reader of Popular Science magazine. In the last page or so, they usually had visual clues without words to make useful stuff. I always wanted to create a mathematical puzzle like that ...
2
votes
1answer
101 views

All Aboard..Hop onto the Power Train to reach Destination Unity

Your goal is to reach the destination unity. starting from $3462$ with three intermediate stops. You are allowed to use only 2 mathematical operations..multiplication and Exponentiation. All the ...
21
votes
8answers
3k views

Robots in a spaceship

Xerxes has 6, 7 and 8-arm robots in his spaceship. Unfortunately, the 7-arm robots are misprogrammed and everything they say is a lie. The other robots are fine, they always speak the truth. Once ...
4
votes
4answers
438 views

Simple logic puzzle

We think of an island inhabited by rogues and knights. Rogues are always lying, knights always speak the truth. One day 12 islanders come together among which is at least one knight and at ...
2
votes
1answer
70 views

Primes from the Pan Digital

Pan Digital Number is the smallest with all the digits 1 to 9 with no repeats. When looking forwards or backwards, eleven Primes can be extracted from that number preserving the same sequence. Among ...
5
votes
3answers
181 views

When is the truth spoken?

A thief speaks truth two days a week alternatively ( T F T ). The days are the same for each week. The thief gives these statements on 3 consecutive days : D1 : I lie on Monday and Tuesday. D2 : It'...
7
votes
1answer
142 views

The strange forest

In the forest of change there are strange creatures: 17 puzzs, 55 lings and 6 stacs. If one species meets the other, then they become the third. For example: If a puzz meets a stac, then they ...