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Questions tagged [puzzle]

For questions about the mathematical principles behind puzzle, games, riddles, or their possible solutions. Questions that are not strictly mathematical in nature should be asked on Puzzling Stack Exchange.

Many puzzles, games, and riddles are based on mathematical concepts. This tag is for questions that ask about the mathematics behind a puzzle, game, or riddle, or about the solutions to mathematical puzzles.

If you already know the answer to the puzzle you are posting, you might consider posting your question on Puzzling Stack Exchange, instead. If you do end up posting your question on Mathematics Stack Exchange (MSE), please read the following meta posts on these kinds of questions before asking your question:

If you do end up posting on MSE, please make it clear in your question that you are "puzzling" the community and that you will be answer the question yourself if no one in the community posts your desired solution.

3301 questions
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In $x^{x^{x^{x^{...}}}}=2$, the answer is $x=\sqrt{2}$. Why not also $-\sqrt{2}$?

From this question $$x^{x^{x^{x^{...}}}}=2$$ The answer is clearly $\sqrt{2}$, but I'm curious why it's not also $-\sqrt{2}$. Am I missing something basic?
kitta
  • 165
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math puzzle: 4 digit number times 3

A four-digit number $\overline{abcd}$, and a five-digit number $\overline{efghi}$, where $a,b, c, ..., i$ are from 1-9 and are distinct. We have $\overline{abcd}*3=\overline{efghi}$. What are $a, b, ..., i$? What I have tried: I can deduce that…
maomao
  • 1,201
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The Ages of Mathematician´s sons

Two mathematicians meet and talk: "Do you have a son?" asked the first mathematician. "Yes I actually have three sons, and none of them are twins." answered the second mathematician. "How old are they?" asked the first mathematician. "The product of…
Adam Páltik
  • 316
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A riddle about three children

We have three children: $A$ , $B$ , and $C$. Child $A$ says: "I ate more sweets than $B$ , and $B$ ate more sweets than $C$." Child $B$ says: "$C$ ate more sweets than me , and $C$ also ate more sweets than $A$." Child $C$ says: "$B$ ate more sweets…
dolfi224
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Word Problem Proof? (just for fun, help)

Players $1, 2, 3,\dots, n$ are seated around a table and each has a single penny. Player 1 passes a penny to Player 2, who then passes two pennies to Player 3. Player 3 then passes one penny to Player 4, who passes two pennies to Player 5, and so…
Mr_CryptoPrime
  • 840
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Drawing a figure without lifting the pen

A friend of mine said that if you can draw the figure below without lifting your hand and without going over a piece for a second time, you can do whatever you want. I couldn't do it, no matter how I tried. There's always one piece missing. Is it…
1Spectre1
  • 377
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Given an 8x10 square how many times can a specific word be found

['Y', 'L', 'L', 'A', 'C', 'I', 'H', 'P'], ['L', 'L', 'A', 'C', 'I', 'H', 'P', 'A'], ['L', 'A', 'C', 'I', 'H', 'P', 'A', 'R'], ['A', 'C', 'I', 'H', 'P', 'A', 'R', 'G'], ['C', 'I', 'H', 'P', 'A', 'R', 'G', 'O'], ['I', 'H', 'P', 'A', 'R', 'G',…
Jacob
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Whose hat was taken by P, how and why?

Four brothers go to a dance party. As the leave,each of the brother accidentally takes a hat belonging to another brother and the coat belonging to the third brother. M takes the court belonging to the brother whose hat is taken by P, while P's coat…
yena shah
  • 55
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Problems About Logic: Alice, Bob, and Charlie, who is the one that telling lie?

I have problem to solve, Three people have their own statement: Alice : If Bob tells lie, then Charlie tells lie too Bob : If Charlie tells lie, then Alice tells lie too Charlie : If Alice tells lie, then Bob tells lie too, Who is the lier? I tried…
Dziban N
  • 25
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Clock losing time puzzle

The question goes as: A wall clock and a Table clock are set to correct time today on 10 pm. The wall clock loses 3 minute in 1st hour, 6 minutes in the second hour and 9 minutes in the third hour and so on. The table clock loses 5 minutes in the…
Gokul
  • 514
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1 answer

Chess Knights Puzzle

The goal is to move the pieces so as to gather them all in the same square - in the minimal number of moves. Chess pieces can move as normal. Additionally, whenever the king and one or more knights are placed in the same square, the player may…
Jakob Weisblat
  • 896
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Escalator puzzle equation

I'm trying to understand the escalator puzzle. A man visits a shopping mall almost every day and he walks up an up-going escalator that connects the ground and the first floor. If he walks up the escalator step by step it takes him 16 steps to…
temporary_user_name
  • 693
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How many solutions does this Numeric puzzle have?

Numeric puzzle $$\text{Happy} - \text{new} - \text{year} = 2018$$ where each letter corresponds to a single digit. How many solutions does this equation have?
Arbron
  • 41
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Reasoning and Aptitude

Please guide me on what conclusions can I draw from the following information Nine people are standing in a $3\times3$ matrix arrangement. Rajat is the tallest among the shortest persons in each row. Sanket is the shortest among the tallest persons…
user3653788
  • 15
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Gift Exchange Puzzle

Five friends - Alex, Becky, Claire, Devin, and Edgar - are participating in a gift exchange. The friends are sitting in alphabetical order around a hat. Each person writes their name on a piece of paper and throws it into the hat. The rules of the…
Foo Barrigno
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