Deduction

Deduction is a pure elimination puzzle. A few clues describe one secret number · "it is even", "it is greater than 30", "its digits add up to 9" · and a row of candidate numbers sits below. Every wrong option breaks at least one clue, so the answer is the single number left standing once you cross the others out.

What it trains. The elimination method · ruling out possibilities until one remains · is the backbone of logical reasoning, from Sudoku to detective work to scientific hypothesis testing. Holding several constraints in mind at once and testing each candidate against all of them is exactly the skill this drills.

Streak format. Each correct deduction advances your streak; one wrong answer ends the run. As the difficulty climbs the numbers get bigger and more clues are layered on, so you have to combine more constraints to land the single answer.

Printable as a worksheet · the clues and options are pure text, so it prints with a clean answer key. Translated into all 25 languages. Part of the PlayMemorize family, runs in your browser and works offline as a Progressive Web App.