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).
1,935
questions
9
votes
3answers
178 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
164 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
176 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
133 views
we are five we have three thousand four hundred fifty who are we? [on hold]
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
113 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
244 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
224 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 ...
0
votes
0answers
54 views
Word problem help regarding Sin and angles [closed]
My teacher gave me this problem.
There is a triangle with angle with 30 degrees (so opp/hyp = 0.5)
This specific triangle has an area equal to it's perimeter.
All I got furthest to was that hyp is ...
2
votes
2answers
200 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
92 views
2
votes
1answer
174 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
115 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
245 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
725 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
105 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
46 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
466 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
97 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
112 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
157 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
73 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
686 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
234 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
98 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
426 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
68 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
168 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
132 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 ...
15
votes
3answers
2k views
The warming up game
The theater group began today with a warming up game.
Everyone has been assigned a role and is now either a bad guy who always lies, or a good guy who always tells the truth.
Max, who comes late, ...
12
votes
1answer
449 views
Resolve this Fibonacci Relationship
$Given$:
$A$, $B$, $C$, $E$, $F$ are distinct digits varying from $1$ to $9$.
$A$ is a Fibonacci number.
$BB$, $BC$, $EF$ are concatenated Numbers.
$Relationship$:
$(A*BB)*(BC)^2$ = $(EF)^2- B$
...
4
votes
3answers
181 views
Missing informations for the architect
An architect wants to plan the creation of a house, but he has only two perspectives, one from the left and one from the front.
The house consists of concrete cubes. All concrete cubes must be ...
3
votes
1answer
108 views
Fill 5 x 5 grid
In each cell of a 5 × 5 square there is a token that is black on
one side and white on the other. Initially all tokens are placed
with the white side facing up. On each move three tokens in
...
3
votes
2answers
188 views
Help me solve this question from a culture fair IQ test? [closed]
Cannot wrap my head around these 2, please also tell me what the logic is? For the 2nd one I think it might be a water droplet shape? But not sure about the logic. Thank you
3
votes
2answers
119 views
Badminton in vacation
During their holidays Martina, Karl and Jim played badminton every day.
The winner of each match continues to play in the next match against the one who just had a break, while the loser of this ...
19
votes
2answers
1k views
Miss Toad and her frogs
Miss Toad owns a lot of frogs. These frogs are all looking the same, but they can be either mad or nicely.
If a mad frog is in a room with 3 nicely frogs, then he turns red, because he is ashamed.
...
2
votes
1answer
95 views
Resolve these Highly Narcissistic Relations
$U$, $V$, $C$ , $D$ , $E$, $F$, $G$, $H$, are distinct digits, varying from 1 to 9.
$UVCD$, $EFGHD$, $EHHEV$ are concatenated numbers.
Please deduce these with concise reasoning from the given ...
2
votes
1answer
113 views
Help the IT guy heal one of his hard drives [duplicate]
There are $64$ hard drives each with one extra bit ("flag"), the value of which you don't know (it can be '$0$' or '$1$'). One hard drive is infected with virus that you need to heal.
You have two ...
3
votes
1answer
95 views
Take out one Third..Keep Two Third..To Total Ten
There are total 36 numbers in the grid shown in the picture.
Cross out 12 of them and keep 24 of them.
Sum of the rest of the numbers should total 10 for each row and column.
-7
votes
4answers
123 views
What am I to A? | Riddle
If teresa's daughter is my daughter's mother, what am I to teresa?
Grandmother
Mother
Granddaughter
I am teresa
0
votes
2answers
82 views
It is not as Simple as it Looks to get the right Alignment
Of these US Coins (Quarter and Dime Combo).
Initial arrangement of the coins as shown in the picture is as follows... Q D Q D Q D Q
Objective is to attain the final configuration... Q Q Q Q D D D.
...
-6
votes
1answer
69 views
Give these Digits their own Place..Place them Right
In their own Circle.
Such that the arrows point to successive numbers . Start with 1 and end with 9. There might be more arrows than necessary.
Find the solution with least number of arrows ignored.
2
votes
2answers
338 views
How many codes are possible?
The line - codes we are looking at consist of black and red lines. These lines can have width 1 or 2. Black and red lines are taking turns, black line, red line, black line, ... The code ends and ...
3
votes
2answers
299 views
5 cars in a roundabout traffic
Five cars are driving in a roundabout traffic at the same moment. Each comes from an other direction, and drives less than one full round. Also each car leave the roundabout traffic in an other ...
4
votes
1answer
90 views
Numbers 1 to 10 in the circles
The objective is to enter the numbers 1,2,3,4,5,6,7,8,9,10 in the blue circles. Doing this, the sum of the numbers has to be equal in the three connected rectangles (a rectangle consists of 4 ...
6
votes
2answers
350 views
Go Get the Six Six-Pack
And fill with right Mathematical operands and enjoy.
Six Relations shown in the pictures are missing the right operands.
You can only use plus, minus, multiplication, division signs in between the ...
