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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My Friend's Salary [closed]
My salary is $2,000, I am of Armenian descent and am 31 years old.
However my friend, is of German descent and is 26 but he earns $8,000.
I think this is blatant discrimination but can you guys find ...
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9
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Connect Wall With A Fun Fact
Instructions:
• Four mystery words are replaced with a double question mark and must be deduced by the solver. NOTE: words are not necessarily in alphabetical order after the mystery words are ...
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How many uncoordinated cubers does it take to solve a Rubik's cube with multiple solutions?
Inspired by Rubik's cubes with multiple sets of colors or stickers. Suppose there's a Rubik's cube with multiple solutions (represented by multiple sets of colors) made with special paint that reflect ...
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What’s the highest salary the greedy king can arrange for himself?
A little kingdom contains 66 people, a king and 65 citizens. Each of them, including the king, has a salary of one gold piece. When democracy comes, the king is denied a vote, but he has the power to ...
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Can you arrange 25 whole numbers (not necessarily all different) so that the sum of any three successive terms is even but the sum of all 25 is odd?
To allow new users to solve this puzzle and earn reputation points, I encourage all users whose reputation is 200 or more to not post an answer until 48 hours after this question is posted. Thank you!
...
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Next date in the future such that all 8 digits of MM/DD/YYYY are all different and the product of MM, DD and YY is equal to YYYY
This problem is a little variation from this problem I made 2 months ago, which is inspired from this post.
When is the next date in the future such that all 8 digits of MM/DD/YYYY are all different ...
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2
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In a circular tray of radius 1, arrange coins of radius 1/2, 1/3, 1/4, 1/5 so that none of them can move independently
In a circular tray of radius $1$, arrange coins of radius $\frac12,\frac13,\frac14,\frac15$ - at least one of each, and no other kind of coin - so that none of them can move independently, i.e. if any ...
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Strategy for determining graph traversal rules yielding exactly one distinct graph traversal under every permutation [closed]
I am looking for advice/guidance/solutions which can help me with the following problem:
Imagine a spatial graph in the x,y-plane arranged in an m x n grid
e.g. a 4x4 grid
Each vertex in the graph ...
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2
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Internet Problem Solving Contest 2017 - Problem M
I was practising interesting problems from past problem solving contests when I found this one. I guess that I should find some hash functions to find the candidates and check them by hand. I tried ...
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Reconstructing Euro results
In the group stage of this year's UEFA European Football Championship, teams compete within six groups of four teams each. Each group plays a round-robin tournament, in which each team plays three ...
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Find the value of '?' in 4x4 table of numbers [closed]
Solve for ?
50
15
10
60
45
31
5
87
40
22
42
?
9
4
3
14
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1
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How can eight quants learn their average salary without revealing individual salaries? [closed]
Here is a problem from section 2.3 (Thinking Out of the Box) section of the popular book by Xinfeg Zhou titled 'Quant salary':
Quant Salary
Eight quants from different banks are getting together for ...
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How to print Square Oblique Pyramid on paper for folding [closed]
How can I print the diagram for folding paper model of Square Oblique Pyramid given the base width and x and y coordinate of the projection of apex on the base? I am looking for formulae to calculate ...
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Strategy for solving "Hypatian Enigma" puzzle (all lines add to 38)
The "Hypatian Enigma" puzzle consists of 19 hexagonal blocks numbered 1 through 19.
The blocks are arranged in 5 rows. The first and last rows have 3 blocks, the second and fourth row has 4 ...
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votes
2
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Finding a mystery number - with three logicians
Three perfect logicians named A, B and C each select a positive integer and report their number to Mufti.
Mufti writes the sum of the three numbers on one card and the product of the three numbers on ...
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