Questions tagged [mathematics]
A puzzle related to mathematical facts and objects, whose solution needs mathematical arguments. General mathematics questions are off-topic but can be asked on Mathematics Stack Exchange.
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Weighing Coins -- a Different Approach
This is a question of my own devising. You have a double pan scale which will tell you whether 2 coins or 2 groups of coins weigh the same or whether one side is heavier than the other side. You have ...
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What is the maximum number of people who speak only 1 language?
There are 1000 people in a conference. 500 speak English, 500 speak Spanish and 500 speak Hindi. What can be the maximum number of people who speak only 1 language?
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Maximizing row and column products in a 4x4 grid
Using the numbers 1, 2, 3, ... 16 each exactly once, fill each square of a 4x4 grid so that the product of the numbers in each row is a multiple of $N$ and the product of the numbers in each column is ...
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Determine if N is zibbable [closed]
The Zib sequence ${Z_N(M)}$ = $\{{a_i}\}$ is a very simple sequence defined on a pair of numbers $N \in \mathbb{N_{odds}}$, $M \in \mathbb{N}$:
${a_0}$ = $M$
${a_{i+1}}$ = $a_i+N$ if $a_i$ is odd
${...
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How to rotate ten players? [closed]
How to rotate ten card players over two separate tables as equal as possible for four different games?
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Largest prime number erroneously erased when finding all primes less than 1000
Chicharron is a lover of mathematics and once wanted to find all primes less than 1000. He did by the following steps below:
He wrote all the numbers from 2 to 1000.
He circled the number 2 and erased ...
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Can you make 39 using the numbers 5 4 3 2 1 in that order?
Is it mathematically possible to show by some creative way that when you combine the digits 5, 4, 3, 2, 1 in that order using operators (+, -, x, integer division/ floating point division(//) or ...
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Destroying Democracy
There is a square grid of people and two political parties: Red and Yellow. The grid is split into districts, with the following rules:
All districts must be rectangles
Each voter must be in exactly ...
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What's the price of banana?
An Iranian merchant has immigrated to the USA and opens his fruit store there.
He labels his fruits in both Persian and English with the costs in dollars:
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Fill the triangular grid using the digits 1-9 subject to the constraints provided
Fill the grid using the digits 1-9 four times each. No row or column can contain the same digit more than once. The total of each row and column is provided, as well as clues to the numbers forming ...
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Are you radical enough to solve this SURDOKU?
All "surds" represent whole numbers smaller than 15, and the same number is never used twice with the same index. (It's a sudoku.)
Attribution: PUZZLEBOMB.co.uk. Puzzles by @stecks & @...
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decode the hiring puzzle?
There is a puzzle on this site Socket_Supply_Co
a00fba3af1ffc09,
Rabbit hole's enigma calls,
Puzzle unfolds deep.
I tried to decode the first line which is ...
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8x8 grid with no unmarked L-pentomino
What is the minimum number of cells on a 8x8 chessboard that need to be marked so that the unmarked cells do not contain an L-pentomino?
An L-pentomino looks like
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Radioactive rocks and an unusual track [closed]
Yesterday, Matt and Rachel jogged for a half hour around a circular track with a
radius of 100 meters. In that time, Matt ran 10 laps and Rachel ran 7 laps. Each
started and stopped in the same ...
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