Mathematics Stack Exchange
Mathematics Stack Exchange

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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Could you generate any positive number given only a few specific operators and operands?

I saw a joke UI on another site where it was a phone number input using only the below commands: $$n \times 3 \\ n + 7 \\ n \div 5 \\ n - 2 \\ \lfloor n \rfloor \\ \sqrt{n} \\ n^2 \\ \log_{10}(n) $$ Where $n$ is the current number (begins at $0$). I…
gator
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Alphametics puzzle, given numbers that are prime and square.

I have been trying puzzle solving recently and came across this problem (sorry if this is not entirely appropriate on a maths stack exchange, I have also posted this on the puzzle one). Any hints on how to do this? So far, I have found that N, R…
Jamminermit
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Smallest size of set of real numbers such that the sum of any seven is strictly positive, and the sum of any eleven is strictly negative

So I just got asked a question that riddled me. If you have a set of real numbers, such that the sum of any 7 numbers from this set is strictly positive and the sum of any 11 numbers from this set is strictly negative, then what is the smallest…
Rich
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Q*Bert minimum moves to solve level

In the old video game Q*Bert, Q*Bert hops on squares on a 7-high pyramid to try to change them a certain color. Q*Bert can also jump off the edge onto discs, which drop him back on the top square, which then changes. In my sample level(s) I also…
aschultz
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How do you substitute integers 0-9 in this equation to solve it?

The goal of the word math problem is to assign each letter an integer value, 0-9. Only one number per letter Problem: WORMHOLE/IDIOT=HEM Example: MAKE+KEYS=PSST In this example: E=3, K+1, A=4, Y=5, S=7, T=0, M=8, and P=9
Oompa Loompa
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How quickly is it possible to put a blank jigsaw puzzle together.

My 12 year old nephew asked me a hypothetical question that asks if I would be willing to take a bet about puzzling a 1000 piece blank jigzaw puzzle in a month's time. If I succeed I win a large sum of money, if I lose I have to pay the sum. For…
Sigmundur
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Total number of bars in a castle puzzle

I stumbled upon a mathematical/logical puzzle that I figured was impossible to solve. Here it is, straight from puzzles SE: Two friends, Mark and Rose, are very famous logicians; they are so clever that they can deduce any logic connection possible…
Sejanus
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Extending the general solution to the "Four fours" problem

The four fours puzzle is, given a number $n$, how can you represent $n$ with common (or more specifically, elementary) mathematical functions and 4 or less occurrences of the digit 4. On the wikipedia page, it says there is a general solution to…
Nico A
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Puzzle - reordering people in a line

Eighty players numbered I through $80$ are standing in a row, one behind the other, in the increasing order of their numbers. The physical director of the players performed eight successive inspections of the players and in each of the respective…
Arpit Bajpai
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When are all pairwise sums consecutive?

What finite ascending sequences of integers $(a_1, \cdots, a_n)$, with $a_1 = 0$, are such that the sequence obtained by sorting all the pairwise sums $a_i + a_j\;\;(j > i)$ consists of ${n \choose 2}$ distinct consecutive integers? One example is…
kjo
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Explanation of a solved puzzle' solution

This question pertains to the solution of a puzzle offered some times ago here. However, as suggested by the author of the original answer, it might be a good idea to rewrite a more fleshed out version of his answer as it has become difficult to…
user1963
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Seeing a pattern (puzzle)

Does someone see a pattern?: 1 11 21 1211 111221 312211 13112221 1113213211 31131211131221 13211311123113112211 111312211331121321113212221
user294478
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1 answer

Totally puzzled by calculating distance I'd be behind Usain Bolt if I competed with him

I'm a simple man living his life and enjoying every moment I get. I don't know much mathematics and I need a little bit of help figuring out the following puzzle. Today I found out about world champion runner Usain Bolt. He can run 200 meters in…
bodacydo
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An alien comes to Earth and says $7\times7=41$. How many fingers does he have?

I understand this sounds ridiculous at first but I got asked this question by a supply teacher $3$ days ago and I haven't been able to answer it so it's driving me insane. I got given two hints: It's over $10$ fingers because we have $10$ fingers…
Fed
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A river crossing puzzle with relatively prime problem

I want to share a problem on a facebook group : https://www.facebook.com/groups/419858384791916/permalink/640398286071257/ 99 people, numbered 2 to 100, are all on one side of a river and wish to reach the other side. There is a single boat with…
kong
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