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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Number puzzle, number arrangement

Arrange all of the digits from the numbers 1 through 15 in such a order that the sum of any adjacent pair is a perfect square. No repeats. I can be staring at those number for days. But I wonder if there is a trick.
most venerable sir
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Answer to popular mathematical riddle

I recently run into a question that asked me to find a number $n$ if for $k$ times, $n$ has been halved and subtracted $0.5$ and, at the end, $n$ becomes $0$. I don't know if this is of any relevance but the question was about people in a bus and in…
probablynotfranco
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Find the missing term?

/\ / \ 5 / 12 \ 6 /______\ 4 /\ / \ 6 / 21 \ 7 /______\ 5 /\ / \ 4 / ? \ 8 /______\ 10 The question…
Man_From_India
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Keys and key hole puzzle odds.

You have 13 keys... and 5 key holes.... 5 keys work in the 5 key holes... In random chance what are the odds of getting randomly all 5 keys in the right key holes on the first atempt. Bonus. getting 4right and 1 wrong on on the first attempt. And…
dan
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Riddle about amusement park profit in relation to ticket's price

Price of the ticket at amusement park was cut down. In the result there was 50% more visitors in the park. At the same time profit from tickets' sale raised by 20%. What was the rebate for the ticket(how much ticket's price went down)? My…
Yoda
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Riddle about number of children Mr. A,B,C have

I have a riddle and I am stuck with it second day. Mr. A,B,C have in total 6 children: 5 sons and 1 daughter. John has one child more than Mr.B. Thomas has the same number of childrean as Peter and John have in total(summed up). Mr.C has the same…
Yoda
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Ant on a square

There is a square of side $1 m$ and an ant has to cross diagonally. However, it chooses to walk along the boundary so the distance covered by it is $2m$ and not $\sqrt{2} m$. This it does in two moves. Now the ant decides to walk along the one side…
Artemisia
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Cut circle with straight lines

Problem: To cut a circle with $n$ straight lines into the greatest number of possible parts. What is the greatest number and how can you prove it is optimal?
marshall
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Four lines are drawn on a plane with no two parallel....

I am stuck on the following problem: Four lines are drawn on a plane with no two parallel and no three concurrent.Lines are drawn joining the points of intersection of the previous four lines. Number of new lines obtained this way is :…
learner
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Can someone please explain the catch behind this question?

Possible Duplicate: Riddle (simple arithmetic problem/illusion) I don't know if this is off-topic, but I recently saw this riddle, which I believe many of you have seen before: There are three men travelling. They stop at a motel for the…
Cryst
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Help me with this riddle.

We have two variables from 2 to 99. Their sum is A. Their product is B. I know A, the other person knows B. We have to get the numbers without asking each other. But I call the other person and say that I have no idea what these numbers can be. The…
Misho Metreveli
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Exchange without changes

There are three type of amount currencies that is less than 10 namely: 1, 2, and 5. You are going to drug store, supermarket, restaurant today where you will have three exchanges(buy medicine, buy goods, eat food ). For convenience you don't want to…
didxga
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Is such transformation for a given array possible?

My friend asked me this question and I am not able to solve it even I am not getting how to think about such problem. Please provide a good method? Given $n$ numbers, you can perform the following operation any number of times : Choose any subset of…
kumar
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Getting the right mathematical representation for a riddle

I haven't written any mathematical equation in years, so I struggled to solve this riddle this morning. "2 groups, one consisting of religious people, the other of scientists, meet to discuss if Adam and Eve were the origin of mankind or if…
SaschaM78
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Does this block puzzle approximate a continuous function?

I have a question related to the following process. Take a single square block and place it in the bottom left of a grid. ▄ Then take whatever there is in the grid, shift it to the right by one and drop it on top of the existing blocks, essentially…
Dachs Luchsinger
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