Logic grids: match people and professions
Learn to solve one-to-one matching puzzles with a grid and try 50 uniquely solvable challenges.
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Clear, organized learning paths that build strong foundations in mathematics and computer science.
Logic
Five clues, one word: verbal logic
Discover how one word connects five clues, with examples, strategies and 36 puzzles in the interactive lab.
Read25 epistemic logic and deduction puzzles
Hats, statements, strategies and information: 25 challenges with hidden, explained solutions.
Read50 hard puzzles that test logic, mathematics and intuition
Scales, coins, hourglasses, strategies and paradoxes: fifty challenges whose results and explanations stay hidden until you choose to reveal them.
Read50 logic games that trick the mind
Fifty questions built on ambiguity, mental shortcuts and lapses of attention. Answer first, then reveal the result and explanation.
ReadSix Kordemsky puzzles: mathematics almost without calculation
Shoes, apples, trees, target shooting, a purchase and logs: six problems where the right reasoning matters more than lengthy calculations.
ReadThe pigeonhole principle: theory, method and 25 worked problems
From the box principle to remainders, geometry and subsequences: 25 problems with solutions to reveal after trying.
Read25 games: sometimes lying, sometimes telling the truth
Alternating liars, limited truths, particular days and conditional behaviors. Each game is followed immediately by its solution and explanation.
Read25 paradoxical logic puzzles
Question, immediate solution and explanation. All examples are formulated coherently.
Read15 problems about brothers and sisters
Solutions with and without equations, with explicit construction of the pairs
ReadBefore calculating: recognize the family of a problem
Ten strategies for recognizing the structure of problems: guided examples, a simulated lesson and three exercises with hidden solutions.
ReadLateral thinking: 25 puzzles that challenge your assumptions
Reworked classics and new situations: 25 puzzles with hidden hints and explanations, separating facts, assumptions and possible answers.
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