Questions tagged [logical-deduction]
A puzzle that requires formal logical deduction to arrive at the solution. This suggests more than merely reasoning through clues to find an answer (you might want [situation] for that).
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The Planet of over a Hundred Moons
What does this abstract picture represent?
Fill the answers to the clues into this grid for the answer:
(Straight lines, standard wordsearch style)
1. Go at train tracks with a shovel (3 2)
2. Set ...
- 27.7k
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Another four 3D masyu
This puzzle is inspired and descended from Brain-breaking 3D masyu
Here the exact copy of rules, for convenience:
This is a three-dimensional masyu puzzle.1 The five squares depict the layers of a $...
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A Difficult Colombian Sudoku?
This Colombian Sudoku is by Xavier Castillo. Usual Sudoku rules apply. Additionally, digits on each of the two diagonals must all be different.
The dots outside the board above indicate how many cells ...
- 19.3k
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🐍 In the Loop 🐍
Follow the ouroboros down valleys and over mountains. Is it even going anywhere?
EDIT (7 days after initial posting): The grid and Penpa+ link have been updated to an easier version, with more numbers ...
- 1,054
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Help with Star Battle puzzle
I made it through all the easy levels without ever having to consciously divide the whole grid into specific regions. I've seen that this is a common technique, but it confuses me even more when ...
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A Crabby Sudoku
I present a *deep breath* Even-Odd TetroThermoDoku. From the back of the name to the front:
Rules
Sudoku: Fill each cell with a digit 1-9 such that no number repeats in any row, column, or 3x3 heavy-...
- 10.4k
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Plumbing Issues
This is part 59 of the puzzle series Around the World in Many Days. Each part is solvable on its own.
Dear Puzzling,
This is a Pipes puzzle (also known as Net, FreeNet and NetWalk). Rotate some cells ...
- 78.6k
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A small board-puzzle
Place pieces (red) on the board, so every piece is adjacent to 4, 5 or 6 other pieces.
I've created this puzzle myself playing around with cellular automatons.
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Masyu: Four Colours
Draw four separate loops in the grid, one blue, one green, one grey and one red. Loops connect centres of cells horizontally and vertically and cannot cross over themselves or share any cell with each ...
- 78.6k
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Logic and Geometry Problem #6
Is it possible for a deadlock to occur in Necklace? Can there be a square on which neither Red nor Blue can place a stone?
If it is possible, I need to see an example of that.
If a deadlock is not ...
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Cover me, I'm going in!
This is part 58 of the puzzle series Around the World in Many Days. Each part is solvable on its own.
Dear Puzzling,
This is a diagramless checkerboard crossword. Empty cells are either blue or white;...
- 78.6k
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What can I deduce about this daily Skyscrapers? (Mar. 18, 2024, 5x5 Easy)
So I have been using a site called Brain Bashers, which is a site filled with logical deduction puzzles, because I like trying to master different logical deduction puzzle types.
I have finished the ...
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a few signposts
Assign an integer (1 through 16) to each cell so that:
16 is in the cell with the star; and
each integer's arrow points to its successor (i.e. the next integer), though not necessarily in the ...
- 12.9k
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Product = Sum Sudoku (Royal Statistical Society Christmas Quiz 2023)
Normal Sudoku rules for this grid size apply. The product of the numbers on each pink diagonal equals the sum of the numbers in the blue square.
This puzzle is from the now closed contest at: https:/...
- 12.5k