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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
vote
1answer
54 views

Four Doors, One Escape

You are trapped in a room with four adjacent doors upon a wall. On each door is one of the first letters of the alphabet, in order, from left to right. You know that one of the doors leads to freedom, ...
3
votes
3answers
63 views

Three knights or knaves, three different hair colors

In a group of three people (A, B and C), everyone has a different hair color (blond, black or brown, not necessarily in this order) and everyone may be either a knight (always telling the truth) or a ...
0
votes
0answers
53 views

Words sequence please help [on hold]

My friend gave those word sequences,you basically need to find the word that best fit the x line:trigon::circle:x Cone:ellipse::circle:x Primus:current::ultimo:x Cube:tetrapod::tetrahedron:x ...
6
votes
1answer
116 views

Statue Park: Five

This is a Statue Park puzzle (originally constructed for the 2019 24-Hour Puzzle Championship, as part of a Tarot card themed set -- no prizes for guessing which rank this puzzle was). Rules of ...
2
votes
1answer
75 views

Puzzling Palindromic Year with Pleasing Palindromic Expression.. Please find them

No computers, calculators or searches. Given: The number is a Palindromic year. $PQ$ is a concatenated number. $ U , V $ are two distinct positive integers Expressed as $ PQ ^ U + PQ ^ V + ...
0
votes
2answers
45 views

Uvc with Lots of Magic… Enjoy the Show!

Puzzling Weekend! UVc is back again with Lots of Magic... Enjoy the Show! Given: LOTS is being multiplied by F to yield MAGIC. Digit 0 to 9 are all represented by ten different letters in this ...
3
votes
2answers
105 views

Find the values of U, V, C based on the given relationship…useful for upcoming puzzles

Given: U, V, C are 3 distinct digits..values can vary from 1 to 9. CU is a concatenated number Solve for U,V, C from the following relationship: $U^V$ X $V^U $ = $CU $ This will give some basis ...
2
votes
2answers
171 views

Cathy’s Composite party is powered by three Prime Pals. Can you find them?

Given: A, B, C are 3 distinct primes. Find the smallest composite number Y that satisfies the relation: $ Y = A ^ C + B ^ B + C ^ A $
5
votes
1answer
171 views

Hiker’s Cabin Mystery | Pt. V

Be sure to see the previous parts and solve Part II because that’s the only one without an answer! After you’ve unlocked the mystery of the map, you go to (Solution to Part IV) to try and find this ...
0
votes
1answer
126 views

Every Answer To All Puzzles Here - Secret Found

BREAKING NEWS: The magic stone which reveals all answers on this site has been located! The only known photograph of the stone: The Stack Exchange Adventure Club has received word that the "All ...
2
votes
3answers
2k views

Should I take the antidote? [on hold]

A new disease has been discovered in the world, it is called Blue. Statistically 1:1000 people in the world has it and it makes your whole skin blue in a few weeks after getting the disease but not ...
0
votes
0answers
87 views

Join the Fun at Jack’s Casino to get a shot at Jackpot

Jack’s casino dealers are not all prime. But, he gives better odds to get the daily Jackpot by revealing lot more numbers in the sequence in play. That way his Casino is much better than Cryptic ...
0
votes
1answer
62 views

Find the missing parking space number [duplicate]

Each space in this parking area is numbered. The parked car covers one of the numbers. What is the number? For reference, the parking numbers are $16,06,68,88,X,98$ where $X$ is the hidden number.
4
votes
2answers
183 views

The CompuTaria Quest - A young Wizard's journey

Once Upon A Time In A Land FAR, FAR Away... Our adventure begins in the enchanted land called "CompuTaria". You are, "Binaryian" a 3rd year Wizard In Training. Today began like any other day - you ...
-7
votes
2answers
135 views

The Guys - Logic #3 - The Casino

Oh boy, the guys went to the casino.. Let's see what these three are up to tonight. I wonder if going to the casino was a good idea?? Maybe for a couple of them. Start the two minute timer... The ...
-3
votes
1answer
111 views

The Guys - Logic #1 - Comics

Welcome to the first in a series of quick logic puzzles. The stories behind the puzzles follow 3 guys who are life long friends, went to school together, and now work in the IT field together in Tampa....
-5
votes
1answer
92 views

The Guys - Logic #2 : Ways to work

So the guys are back. This time, they decide to change up their way to work. Let's see what they're up to... Start the two minute timer... 1. Since Anthony and Charles weren't taking the bus today, ...
41
votes
11answers
8k views

3 doors, three guards, one stone

You are in a room with three doors. You find out that behind two of these doors, the darkest pit of hell is waiting for you to make a mistake. The other door leads to heaven, where you obviously want ...
12
votes
12answers
5k views

Coin Game with infinite paradox

Here’s the puzzle/problem: Let’s presume we are best friends. I own the house next to you. I make a gaming proposition along the following lines: You throw a coin over and over again. So long as it ...
2
votes
2answers
95 views

Find the set of letters corresponding to a set of words

Each word in the following list corresponds to one letter: rôle résumé Jalapeño xoriço ö führer The combination of letters can be represented as ----uu Here, the -'s represent the missing letters. ...
17
votes
2answers
2k views

We are two immediate neighbors who forged our own powers to form concatenated relationship. Who are we?

Our concatenated number is $ \overline{ABAC}, $ where $ A, B, C $ are all positive digits (1 - 9). Our relationship is $$ \overline{ABAC} = A^A + B^B + A^A + C^C $$ Who are we?
5
votes
1answer
180 views

Hiker’s Cabin Mystery | Pt. IV

You’ve gotten into his computer and opened the correct file. Ready to read? The file turned out to be an image... of a map. Where is our mystery hiker hiding out and how do you know?
5
votes
1answer
118 views

Find the immediate square dancing neighbors, they dance together to perfect square

We live in a community of houses sequentially numbered from 1 to 100. We all love square dancing but only two immediate neighbors are joy to watch. If you concatenate their house numbers, it forms a ...
1
vote
3answers
456 views

Solve for the Number in the number..square..cube relationship

Each letter stands for a distinct digit...no computer or calculator needed. Just pure logic and some mental multiplication. CUBE is a concatenated number and it is a cube. X denotes multiplication. (...
9
votes
1answer
598 views

Narcissistic cube asks who are we?

I am a five digit narcissistic cube who likes to display my root right upfront. I also have hidden it in the back of my four digit cube brother. Who are we?
18
votes
8answers
2k views

30 fake coins out of 99 coins

You are given 99 coins which consists of 30 fake ones. You also have a digital balance scale with perfect precision that shows how much difference between weighs you put on. For example, if you put 10 ...
1
vote
0answers
232 views

Placing rooks on a chessboard

We have a big chessboard with N rows and N columns (numbered 1 through N). Let's denote the square in row r and column c of the chessboard by (r,c). We want to place some rooks on the chessboard in ...
-9
votes
1answer
86 views

Number of days in a normal year expressed with five consecutive positive integers [closed]

Given $D$ is the total number of days in a normal year $a$, $b$ are positive integers $P$, $Q$, $R$, $S$, $T$ are consecutive integers Figure them out by combining the following six expressions ...
-2
votes
3answers
143 views

Complete the following verbal analogy!

MAKE : DALE :: (?) : PALE Hint: pattern recognition or semantical relation (?)=solution containing 4 letters : means 'to' , :: means 'as'
7
votes
1answer
124 views

Emoji-Mutating Machines

I have built twelve emoji-mutating machines, each of which changes one characteristic of an emoji—for example, adding glasses, removing a tear, changing a smile to a frown, and so on. Each machine has ...
-6
votes
1answer
117 views

Guess the words [closed]

Can you figure out the word by only using the first and last letter? WORDS: P _ _ _ Y C _ _ K B _ _ B Those are just some sample words. I will check the ...
60
votes
4answers
4k views

Gerrymandering Puzzle - Rig the Election

The following graphic is a map of the country Mathlandia: You are currently running for reelection, but the polls aren't exactly in your favor. Each square in this grid is a county. Counties with a ...
17
votes
4answers
1k views

Single Colour Mastermind Problem

Imagine we're playing a game of mastermind with the usual eight colours, only this version has six holes across in which to place colours. And to make it easier for you I tell you that I have filled ...
56
votes
2answers
8k views

It's getting harder and harder not to offend anyone

Andy, Bob and Chuck are old friends meeting for the first time in years. Scene 1: At the intersection ANDY: Hey guys! Long time no see! BOB: Hey, nice to see you, Andy! Have you seen Chuck? Is ...
1
vote
3answers
221 views

Can someone solve this kakuro?

Can someone solve this? Please tell me how you did it. Source: Puzzle Page app
6
votes
1answer
208 views

Dividing the gold

There is a king and 3 women in a castle. One day, the king give 3 women a total of 100 golds. He said that each woman can propose an idea to share the gold among themselves. If the proposal passed ...
3
votes
2answers
127 views

SafeCracker #1 - Look who's talking

The Plot You work for a tech company in Tampa, FL. Recently there was a break-in, and the company's trade secrets were stolen. Company PI have tracked the briefcase containing the secrets to the ...
15
votes
2answers
2k views

Virus Detected - Please execute anti-virus code

Virus Detected!!! Your computer, which is represented by the grid pictured, has been infected. The bugs are clearly marked. It's your job to inject your awesome anti-virus code in the proper computer ...
1
vote
1answer
85 views

The Walking StackMan [closed]

Simply figure out how long I had to walk... Ps. Stop googling to find similar answers! I want to see you challenge yourself, especially our younger crowd. :)
0
votes
1answer
69 views

Place Your Bets 3 , last of the series

A harder sequence to figure out... What are the next 4 cards, including suits?
1
vote
1answer
50 views

Place Your Bets 2 - In sequence, of course

Your Cards... You have to figure out what the next row of 4 cards will be. There is a pattern in there somewhere, promise. Good Luck
2
votes
1answer
79 views

Place Your Bets - in sequence, of course

Your Puzzle There is some sort of pattern in cards below. Simply figure out what the next card should be. Note: You cannot re-use a card already in play.
3
votes
2answers
77 views

A Wine Problem for Puzzlers [duplicate]

Simple Follow the instructions on the label. In case you the image is too small, Given three bottles: 8, 5 and 3 liters capacity, divide 8 liters in half (4 + 4 liters) with the minimum number of ...
-4
votes
1answer
181 views

Write an equation using constants e, i, pi and phi [closed]

Without using numbers and using only permitted math operators, write an equation using the constants $e$, $i$, $\pi$ and $\phi$. Allowed operators..exponent...multiplication..subtraction...only. Use ...
-1
votes
1answer
78 views

The Puzzle of Puzzles - Pieces of Logic

The Story Johnny has added several new jigsaw puzzles to his somewhat large, and unusual collection this year. He likes Computer related puzzles, and the outdoors, as well. Your job, Determine each ...
2
votes
0answers
103 views

The Bad Clue Puzzle

The Jumbled Story Johnny might have had a couple beers when putting this one together. What he intended was a logic puzzle of friends, their favorite classic computer system, and how they used to ...
6
votes
2answers
195 views

Top Game Developers

Top Game Developers Back Story Okay fellow puzzlers, I hope you packed your lunch, this one is my most challenging puzzle to date... Johnny is writing an article about some of the top-selling ...
4
votes
2answers
131 views

Hidden Treasure Logic Puzzle

Ok, fellow puzzlers, here is my latest puzzle. They are getting progressively harder. Back Story While snooping around your grandpa’s attic, you came across a bunch of scribbled notes. They were in ...