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1 vote
1 answer
22 views

Friday's Fujisan Problem

4 votes
2 answers
933 views

New York Minute (Jane Street Puzzle)

14 votes
5 answers
6k views

Three airplanes with enough fuel for halfway around the world - how can one make it all the way?

2 votes
0 answers
45 views

What option should replace the question mark?

2 votes
1 answer
94 views

What's the minimum number of airplanes needed for one to make a round-the-world trip?

2 votes
0 answers
277 views

Find all integers n such that $\sqrt{n-4 \sqrt{n-19}}$ is also an integer

16 votes
12 answers
4k views

How to confirm the reader has the right answer without showing the answer?

9 votes
1 answer
496 views

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1 vote
0 answers
41 views

Three planes fuel tanks for less than halfway around the world - how can one plane make it around the world and what is the minimum fuel tank size?

18 votes
8 answers
4k views

Logical puzzle from a math homework for Russian fifth-year school students

2 votes
1 answer
64 views

Tetromino tilings of a 4x5 rectangle with minimal diversity

6 votes
3 answers
249 views

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11 votes
3 answers
1k views
+50

I need help with this IQ test puzzle I found online

13 votes
3 answers
282 views

Look at me - a number sequence

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