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
0
votes
2 answers

Puzzle with twins

Dying someone appointed in the will the following: If his pregnant wife giving birth to a son , then she will inherit 1/3 of the estate and his son 2/3 . If giving birth to daughter , then she would inherit 2/3 of the property and the daughter 1/3…
Paris Lamp
  • 578
0
votes
2 answers

Nine same balls with one heavier

There are nine same balls,which all weigh the same except one , which is heavier than each others from the rest. How we can with just two weighings to find out which is the heavier ball?(We are using scale with two discs) Could anyone help me with…
Legolas
  • 361
  • 1
  • 11
0
votes
0 answers

How to find the function?

I need to find a function that takes two integers as input and outputs an integer. Input : $28$ $1$ Output : $68$ Input : $39$ $1$ Output : $90$ Input : $90$ $1$ Output : $81$ Input : $15$ $2$ Output : $40$ Input : $123$ $2$ Output : $17$ Input :…
vidhan
  • 1,020
0
votes
0 answers

Find three ages

Transposing the two digits of A's age gives B's age. The difference between their ages is twice C's age and В is ten times as old as С. What are the three ages? Let A's age be $ab=10a+b$ so B's age is $ba=10b+a$ $$10b+a=10 \times( \text{C's…
Vikram
  • 5,580
0
votes
2 answers

What fraction of the job can be done by one man in one day given 10 men can do a job in 10 days?

If 10 men can do a job in 10 days.What fraction of the job can be done by one man in one day? My Approach: $10$M . $10$D=$100$MD ($10$ men take $10$ days =$100$ man days) $1$ . $1$=$1/100$ (i.e 1 men in 1 day do) Am i right in my approach?
Jack
  • 752
0
votes
1 answer

Determining how many sibling a person has

Ask a fellow student you know to write down on a piece of paper the number of brothers he or she has (if this number is less than $10$) and multiply the result by $2$. Now add $3$ to the result and multiply the new number by $5$. Add to this the…
Caddy Heron
  • 1,249
0
votes
3 answers

A man can cut the grass in $T$ minutes What part of the lawn can be cut in $30$ minutes?

A man can cut the grass in $T$ minutes What part of the lawn can be cut can be cut in $30$ minutes? Options: a) $\frac{30}{T}~~~~$ b) $T-30~~~~$ c) $\frac{T}{30}~~~~$ d) $30-T$ My approach: $1$ man can cut in $T$ minutes. therefore …
justin takro
  • 1,288
0
votes
2 answers

Checkpoints along a Highway

This is a new puzzle I'm creating. Advices welcome. Preliminaries: Imagine a car highway. This highway can be described as the smooth connection of smaller segments consisting of straight lines, and arcs of (for simplicity) circles bending left or…
luchonacho
  • 453
0
votes
0 answers

Strategy for identifying traitors

I started playing the game Lost Dimension recently, and will reproduce the logic problem of the game here. Note that this would therefore have some implied spoilers from that game, although not beyond the first few hours of the game. There are P (P…
Jeremy
  • 1,571
0
votes
2 answers

Relation/ formula to Find the last person standing after removing people alternatively from a line?

Given N number of people, each marked as a number starting from $1$ through N, standing in a straight line where you remove folks alternatively from a line. For example in iteration 1: You would remove $1,3,5...$ Iteration $2 : 2,6,10...$ etc.…
NewbUser
  • 25
0
votes
1 answer

mathematical puzzle

If you have free time you can try to solve next mathematical puzzle. Given are four integers: 1, 3, 4, 6 and also four basic operations: multiplication *, division /, addition +, substruction - Every integer you can use exactly one time, but you can…
Guforu
  • 119
0
votes
1 answer

how many of relatives are female

I am working on this problem but I am not so sure my answer is right. The question is below with multiples choices but there is only is right. Q: c,d,e,f,g,h and i are the father, mothers, aunt, brother, sister, wife and daughter of j, but you don't…
tonytran
  • 117
0
votes
1 answer

If the letters T*(RBJBR)=VPLNT each represented a unique digit, and "RBJBR" was a five digit number, what are possible values for the letters?

If the letters T*(RBJBR)=VPLNT each represented a unique digit, and "RBJBR" was a five digit number, what are possible values for the letters? (Or ONE possible value.) Can we do this in a way that can be done on paper without "guessing and plugging…
badreferences
  • 791
  • 6
  • 7
0
votes
2 answers

Aptitude: Time and Work

6 men can complete a piece of work in 12 days. 8 women can complete the same piece of work in 18 days, whereas 18 children can complete the piece of work in 10 days. 4 men, 12 women and 20 children work together for 2 days. If only men were to…
user1502
  • 127
  • 1
  • 1
  • 7
0
votes
1 answer

Reasoning - Seating Arrangement

Eight fiends P, Q, R, S, T, V, W and Y are sitting around a square table in such a way that four of them sit at four corners of the square while the rest sit in the middle of each of the four sides. The one who sit at the four corners face the…
user1502
  • 127
  • 1
  • 1
  • 7
1 2 3
…
34 35