Tag: brainteasers
Concepts
- Adaptive Versus Pre-Committed Weighing Strategies
- The Lost Boarding Pass Problem
- AM-GM as a Puzzle Tool
- Ants on a Pole and Collision Arguments
- The Arcsine Law: Who Leads a Coin-Flip Race
- Why Averaging Averages Gives the Wrong Answer
- Balance-Scale Weighing Problems
- Bertrand's Chord Paradox
- Binomial Coefficients and Pascal's Triangle
- The Birthday Problem
- How to Attack a Brainteaser
- Buffon's Needle
- Catalan Numbers and Balanced Structures
- Cheryl's Birthday and Iterated Knowledge
- The Chessboard Coin-Flip Prisoner Puzzle
- The Substitution That Collapses the Algebra
- Collision Bounds Beyond the Birthday Problem
- Colouring and Tiling Arguments
- Common Knowledge and the Blue-Eyed Islanders
- Comparing Huge Powers Without a Calculator
- Does This Recursion Converge
- Counting Lattice Paths
- The Coupon-Collector Problem
- Derangements
- Detecting Cycles in an Iterated Sequence
- Cut-and-Rearrange Dissection Puzzles
- Counting the Same Thing Two Ways
- Symmetry Shortcuts for Draws Without Replacement
- Expected Distance Between Two Random Points
- How Long the Gambler's Ruin Game Lasts
- Expected Maximum of n Uniform Draws
- Expected-Value Games
- The Extremal Principle
- Making a Fair Coin From a Biased One
- Cutting a Cake Fairly
- Where Fibonacci Numbers Show Up
- Finding the Median With Few Comparisons
- Fixed Points of Iterated Maps
- Functional Equations
- Gambler's Ruin
- Game Theory Basics
- Geometric Probability Puzzles
- The Guess-Two-Thirds-of-the-Average Game
- The Hardest Logic Puzzle Ever
- The Hat-Check Problem and Expected Fixed Points
- Hat-Colour Problems
- Why HHH Takes Longer to Appear Than HHT
- The Hundred Prisoners and the Boxes
- The Inclusion-Exclusion Principle
- The Indicator-Variable Trick
- Induction and Recursive Structure in Puzzles
- Infinitely Many Hats and the Axiom of Choice
- Counting Information to Bound the Answer
- The Inspection Paradox and the Waiting-for-a-Bus Trap
- Scheduling to Fit the Most Jobs
- Invariants and Monovariants
- The Josephus Problem
- Knights, Knaves and Truth-Tellers
- Light-Bulb Switching Problems
- Solving Logic-Grid Puzzles Systematically
- Mastermind: Deduction From Feedback
- Maximum Regions From n Straight Cuts
- Modular Arithmetic in Puzzles
- The Monty Hall Problem
- The Muddy Children Puzzle
- The Mutilated Chessboard
- Nested Radicals and Infinite Fractions
- Nim and Winning Positions
- Finding the Odd Ball Without Knowing If It Is Heavy or Light
- The Odds Algorithm for Stopping on the Last Success
- One Question, Two Guards, One Door
- Packing Circles and Squares
- Parity Arguments
- Encoding Information With Parity in Hat Puzzles
- Penney's Game and Non-Transitive Patterns
- Estimating Physical Quantities From Scale
- The Piano Tuners Question
- The Pigeonhole Principle
- The Poisoned Wine Bottles and Binary Encoding
- Polya's Urn and Self-Reinforcing Draws
- The Prisoners and the Light Switch
- Prisoners in a Line Guessing Hat Colours
- The Problem of Points: Splitting an Interrupted Bet
- The Chance That Random Points Fit in a Semicircle
- First-Return Probabilities of a Random Walk
- The Rare-Disease Test Puzzle
- Renyi-Ulam: Twenty Questions With a Liar
- River-Crossing and Bridge-Torch Problems
- The Rope Around the Earth
- Rope-Burning and Measuring Time
- Searching a Unimodal Function
- Finding the Second-Best Player in Fewest Matches
- The Secretary Problem and Optimal Stopping
- Self-Referential Quiz Puzzles
- Simpson's Paradox as an Interview Trap
- The Sleeping Beauty Problem
- Solving Linear Recurrences With Characteristic Roots
- Sphere Packing and Wasted Space
- The Spider and the Fly: Unfolding a Box
- The St Petersburg Paradox
- Stars and Bars
- The Sum-and-Product Puzzle
- Summing an Infinite Series in Your Head
- Symmetry Arguments
- Telescoping Sums and Products
- The Three Prisoners Problem
- The Tuesday Boy Variant
- Twenty Questions and the Entropy Bound
- The Two-Envelope Paradox
- Vieta's Formulas: Answering Without Solving
- Golf Balls in a Plane: Volume-Packing Estimates
- Water-Jug Pouring Problems