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| Tags | Companies | ||||
|---|---|---|---|---|---|
| The Costly Re-roll | Probability | Medium | Expected ValueProbability | ||
| The Singular Matrix Hunt | Probability | Medium | Markov ChainsProbability | ||
| Overlapping Triangles | Probability | Easy | CombinatoricsProbability | ||
| The Lucky Wheel | Probability | Easy | Probability | ||
| First to Three | Probability | Medium | Expected ValueProbability | ||
| Switching in the Dark | Brainteasers | Easy | BrainteasersLogic | ||
| Crash Course | Probability | Easy | Probability | ||
| Leveling the Playing Field | Probability | Easy | Discrete Random VariableProbability | ||
| Binary Beginnings and Endings | Probability | Easy | Combinatorics | ||
| The Race to Fifty | Brainteasers | Medium | BrainteasersGames | ||
| The Discounted Bond | Finance | Easy | Brainteasers | ||
| Extinction of the Colony | Probability | Easy | Probability | ||
| Recruiter Roulette | Probability | Easy | Expected ValueProbability | ||
| Symmetric Dice Duel | Probability | Easy | Probability | ||
| Ascending Rolls | Probability | Easy | CombinatoricsProbability | ||
| The Last Green Ball | Probability | Easy | CombinatoricsProbability | ||
| Five Below | Probability | Medium | Expected ValueProbability | ||
| The Limiting Geometric Mean | Probability | Medium | Continuous Random VariableProbability | ||
| Fifth King's Arrival | Probability | Medium | Discrete Random VariableProbability | ||
| Perfectly Angled Polygons | Brainteasers | Easy | BrainteasersCombinatorics | ||
| Eigenvalue of an Outer Product | Pure Math | Hard | Linear Algebra | ||
| Simulating One-Third | Probability | Easy | Expected ValueProbability | ||
| The Last Lily Pad | Probability | Medium | Markov ChainsProbability | ||
| The Costly Re-roll | Probability | Easy | Expected ValueProbability | ||
| Odd Coin Flips | Probability | Medium | Discrete Random VariableProbability | ||
| Ants on a String | Brainteasers | Easy | BrainteasersLogic | ||
| Racing the Rankings | Brainteasers | Easy | BrainteasersLogic | ||
| The Gap of Two | Probability | Medium | Markov ChainsProbability | ||
| The Midnight Bridge | Brainteasers | Easy | BrainteasersLogic | ||
| Building the Perfect Full House | Brainteasers | Medium | GamesProbability | ||
| The Peeled Die | Probability | Medium | Expected ValueProbability | ||
| Normal Differences | Probability | Medium | Continuous Random VariableProbability | ||
| Suit Collector | Probability | Medium | Expected ValueProbability | ||
| Ripples in the Pond | Pure Math | Easy | Calculus | ||
| Prime Triangles on a Circle | Brainteasers | Hard | BrainteasersCombinatorics | ||
| The Volatility Decay | Brainteasers | Easy | Brainteasers | ||
| The Die-Hard Collector | Probability | Easy | Expected ValueProbability | ||
| A Range of Exactly Four | Probability | Medium | CombinatoricsProbability | ||
| The Last Green Apple | Probability | Medium | Expected ValueProbability | ||
| The Leaky Kiddie Pool | Brainteasers | Easy | Brainteasers | ||
| The Backtracking Frog | Probability | Hard | CombinatoricsProbability | ||
| Million Digit Dash | Brainteasers | Medium | BrainteasersCombinatorics | ||
| The Cube Stack | Probability | Easy | Brainteasers | ||
| No Triplets Allowed | Probability | Medium | Combinatorics | ||
| The Marathon Bulb | Probability | Medium | Continuous Random VariableProbability | ||
| Is Chuck-a-Luck Really Lucky? | Probability | Easy | Expected ValueGames | ||
| The Vanishing Gamma | Finance | Easy | Calculus | ||
| Two Standard Deviations Out | Probability | Easy | Probability | ||
| The Bounds of R-Squared | Statistics | Medium | Statistics | ||
| Dice Duel Odds | Probability | Easy | GamesProbability | ||
| Percolating the Grid | Probability | Medium | CombinatoricsProbability | ||
| Second Chance Flips | Probability | Easy | Expected ValueProbability | ||
| Triplets in the Deck | Probability | Medium | CombinatoricsProbability | ||
| Socks in the Dark | Brainteasers | Easy | BrainteasersCombinatorics | ||
| The Covariance Identity | Probability | Easy | ProbabilityStatistics | ||
| Decomposing Variance | Statistics | Easy | Statistics | ||
| The Picky Dinner Guests | Brainteasers | Easy | CombinatoricsLogic | ||
| The Second-Best Bid | Probability | Medium | Expected ValueProbability | ||
| Odd Stars and Bars | Probability | Medium | Combinatorics | ||
| Unlucky Seven | Probability | Medium | Expected ValueProbability | ||
| Sizing Up Squares | Statistics | Medium | CombinatoricsStatistics | ||
| Flooring the Logs | Probability | Medium | Continuous Random VariableProbability | ||
| Divisible Dice | Probability | Easy | CombinatoricsProbability | ||
| The Last Cherry Standing | Probability | Hard | Probability | ||
| Two Steps of Brownian Motion | Pure Math | Easy | ProbabilityStochastic Calculus | ||
| The Matchmaker's Mishap | Probability | Medium | CombinatoricsProbability | ||
| Weighing the Catch | Brainteasers | Easy | Brainteasers | ||
| Modding Eleven | Pure Math | Medium | Brainteasers | ||
| Martingale Maker | Pure Math | Easy | MartingalesStochastic Calculus | ||
| Predicting the Orbs | Probability | Medium | Expected ValueProbability | ||
| The Reciprocal Slope | Statistics | Medium | Statistics | ||
| The Zero Hunt | Brainteasers | Easy | Combinatorics | ||
| Brownian Motion's Integral Variance | Pure Math | Medium | ProbabilityStochastic Calculus | ||
| Odd Hops to the Top | Probability | Medium | Combinatorics | ||
| Tails in Twos | Probability | Medium | CombinatoricsProbability | ||
| Symmetric Normals | Statistics | Easy | Continuous Random VariableProbability | ||
| A Quick Ruin | Probability | Easy | Markov ChainsProbability | ||
| The One-Redraw Dilemma | Probability | Easy | Expected ValueProbability | ||
| First Two or Double One | Probability | Medium | Markov ChainsProbability | ||
| Keep on Rolling | Probability | Easy | Expected ValueProbability | ||
| Cornering the Colors | Probability | Easy | CombinatoricsProbability | ||
| The Chevalier's Dilemma | Brainteasers | Medium | BrainteasersProbability | ||
| The Perfect Square Ceiling | Probability | Hard | Continuous Random VariableProbability | ||
| Taylor's Seventh | Pure Math | Medium | Calculus | ||
| Grandpa's Century-Spanning Birthday | Brainteasers | Medium | BrainteasersLogic | ||
| A Cubic Factorization | Brainteasers | Easy | Brainteasers | ||
| Two Flips Max | Probability | Easy | Discrete Random VariableProbability | ||
| Bacterial Bloom | Brainteasers | Easy | Brainteasers | ||
| Rough Seas | Probability | Easy | Expected ValueProbability | ||
| The Bayesian Test-Taker | Probability | Easy | Probability | ||
| Variance of a Stochastic Integral | Pure Math | Medium | ProbabilityStochastic Calculus | ||
| Alex's Great Escape | Probability | Medium | Expected ValueProbability | ||
| The Price of Perpetuity | Finance | Easy | Calculus | ||
| The Rho of a Put | Finance | Easy | Arbitrage | ||
| Quick ATM Option Pricing | Finance | Medium | ProbabilityStochastic Calculus | ||
| Zeta Covariance Conundrum | Probability | Medium | Discrete Random VariableProbability | ||
| The Lucky Coin | Probability | Easy | Continuous Random VariableProbability | ||
| The Three-Legged Table | Probability | Hard | Continuous Random VariableProbability | ||
| Six-Shooter Speed | Brainteasers | Easy | Brainteasers | ||
| Sizing Up the Dice | Probability | Easy | CombinatoricsProbability | ||
| Make Your Martingale | Pure Math | Easy | MartingalesProbability | ||
| The Productive Pairing | Probability | Medium | Combinatorics | ||
| Steps to Four | Probability | Easy | Combinatorics | ||
| Survivor Coins | Brainteasers | Medium | BrainteasersProbability | ||
| Bound on Covariance | Probability | Easy | Probability | ||
| The Gift Shop Rush | Probability | Easy | Discrete Random VariableProbability | ||
| The Smallest Companion | Probability | Hard | Expected ValueProbability | ||
| Urn Your Keep | Probability | Medium | Expected ValueProbability | ||
| The HTH Waiting Time | Probability | Medium | Expected ValueProbability | ||
| Peaks in a Permutation | Probability | Hard | Expected ValueProbability | ||
| Hunting for Aces | Probability | Medium | Expected ValueProbability | ||
| The Triple Shot | Probability | Easy | Probability | ||
| The Tightest Gap | Probability | Hard | Expected ValueProbability | ||
| The Picky Babysitter | Probability | Medium | Combinatorics | ||
| The Ten-Sided Pig | Probability | Easy | GamesProbability | ||
| Pirate Democracy | Brainteasers | Medium | GamesLogic | ||
| The Daughter Conference | Probability | Easy | Probability | ||
| Home Option Pricing | Probability | Medium | Expected ValueProbability | ||
| Shared Selections | Probability | Hard | CombinatoricsProbability | ||
| The Blue and the Green | Probability | Easy | Discrete Random VariableProbability | ||
| Testing a Fair Coin | Statistics | Easy | ProbabilityStatistics | ||
| Double the Gamma | Finance | Easy | ArbitrageCalculus | ||
| The Divisibility Roll | Probability | Easy | CombinatoricsProbability | ||
| The Modulo Six Marathon | Probability | Medium | Expected ValueProbability | ||
| Dartboard Rings | Probability | Easy | Probability | ||
| The Magic of 37 | Brainteasers | Hard | CombinatoricsLogic | ||
| The Power of One | Probability | Medium | CombinatoricsProbability | ||
| High Fives Before Six | Probability | Medium | Discrete Random VariableProbability | ||
| Summing to Nine | Probability | Medium | Combinatorics | ||
| Diner Dash | Probability | Easy | CombinatoricsProbability | ||
| The Charm of Delta Decay | Finance | Hard | BrainteasersCalculus | ||
| Scaling Variance | Statistics | Easy | ProbabilityStatistics | ||
| Optimal Coin Bias | Probability | Medium | Expected ValueProbability | ||
| The Final Roll | Brainteasers | Easy | Discrete Random VariableProbability | ||
| Lollipop Symmetry | Probability | Easy | CombinatoricsProbability | ||
| The Ace Race | Brainteasers | Medium | CombinatoricsProbability | ||
| Socially Distanced Evens | Probability | Medium | Combinatorics | ||
| Red vs. Blue | Probability | Easy | CombinatoricsProbability | ||
| Symmetric Showdown | Brainteasers | Medium | BrainteasersProbability | ||
| The Fish Counter | Brainteasers | Easy | ProbabilityStatistics | ||
| The Tenth Power | Pure Math | Medium | Linear Algebra | ||
| The Infinite Game of Catch | Probability | Medium | Markov ChainsProbability | ||
| Circular Hop | Probability | Medium | Expected ValueProbability | ||
| Atomic Survival | Probability | Easy | Continuous Random VariableProbability | ||
| Loaded Dice, Fair Sum | Probability | Easy | Probability | ||
| Spot the Itô Error | Pure Math | Medium | Stochastic Calculus | ||
| Smooth Operators | Probability | Medium | CalculusCombinatorics | ||
| Busy Support Lines | Statistics | Easy | Discrete Random VariableProbability | ||
| The First HT | Probability | Medium | Expected ValueProbability | ||
| Bayesian Baby Boom | Statistics | Easy | ProbabilityStatistics | ||
| Snail's Pace | Brainteasers | Easy | Brainteasers | ||
| Exponential of a Gamma | Probability | Medium | Continuous Random VariableProbability | ||
| Dry Weekend Bounds | Probability | Easy | Probability | ||
| The Ordered Five | Probability | Easy | CombinatoricsProbability | ||
| The Race to HHT | Probability | Medium | Markov ChainsProbability | ||
| Put Option Arbitrage | Finance | Medium | Arbitrage | ||
| Triple Head Run | Probability | Easy | CombinatoricsProbability | ||
| American vs. European Call Arbitrage | Finance | Easy | Arbitrage | ||
| Spotify Skepticism | Statistics | Easy | Statistics | ||
| Rook on a Chessboard | Brainteasers | Medium | BrainteasersGames | ||
| The Cubic Martingale | Pure Math | Easy | MartingalesStochastic Calculus | ||
| Birds of a Feather | Probability | Easy | CombinatoricsProbability | ||
| The Lucky Two | Probability | Medium | Expected ValueProbability | ||
| The Infinite Walk | Probability | Medium | Expected ValueProbability | ||
| The Ranking Refund | Probability | Medium | Continuous Random VariableProbability | ||
| The Delta Balance | Finance | Easy | Arbitrage | ||
| The Overlap Odds | Probability | Hard | CombinatoricsProbability | ||
| Sixes and Threes | Brainteasers | Easy | Expected ValueProbability | ||
| Brownian Quadratic Fluctuations | Pure Math | Medium | ProbabilityStochastic Calculus | ||
| Targeting the Optimal Radius | Probability | Easy | Expected ValueProbability | ||
| Rank the Randoms | Probability | Medium | Continuous Random VariableProbability | ||
| The Half-Hour Hedge | Finance | Hard | Stochastic Calculus | ||
| The Boy-Seeking Society | Brainteasers | Easy | BrainteasersProbability | ||
| Call Option Breakeven | Finance | Easy | Brainteasers | ||
| The Floor of Determination | Statistics | Easy | Statistics | ||
| Sweet Combinations | Probability | Medium | CombinatoricsExpected Value | ||
| Rolling a Score of Twenty | Probability | Easy | CombinatoricsProbability | ||
| Scaling the Strike | Finance | Medium | ArbitrageProbability | ||
| The Chess Gambit | Probability | Medium | GamesProbability | ||
| Boy Meets Girl | Probability | Medium | Expected ValueProbability | ||
| The Peak of Four | Probability | Medium | Probability | ||
| Opposites Attract | Probability | Easy | Expected ValueProbability | ||
| Chronological Circle | Probability | Easy | CombinatoricsProbability | ||
| Finite Decimals | Brainteasers | Hard | BrainteasersCalculus | ||
| A Perfect Pair | Probability | Easy | CombinatoricsProbability | ||
| Steinmetz's Secret | Pure Math | Medium | BrainteasersCalculus | ||
| Sizing Up the Bolts | Statistics | Easy | Statistics | ||
| Colosseum Clash | Brainteasers | Hard | GamesProbability | ||
| Two More Coins | Probability | Medium | CombinatoricsProbability | ||
| Mean Combination | Statistics | Easy | Expected ValueProbability | ||
| The Lonely Pair | Probability | Hard | CombinatoricsProbability | ||
| The Great Nugget Partition | Probability | Medium | CombinatoricsProbability | ||
| The Minimalist Divisor | Probability | Medium | Expected ValueProbability | ||
| The Standard Sample | Statistics | Easy | Statistics | ||
| The Power of Evenness | Brainteasers | Medium | BrainteasersCombinatorics | ||
| Counting Cash | Brainteasers | Easy | BrainteasersLogic | ||
| The Pessimistic Locksmith | Brainteasers | Easy | BrainteasersCombinatorics | ||
| Prime Janitors | Brainteasers | Hard | BrainteasersCombinatorics | ||
| The Greedy Pirate Standoff | Brainteasers | Easy | BrainteasersCombinatorics | ||
| Binary Put-Call Parity | Finance | Easy | Arbitrage | ||
| Turtles All the Way Down | Probability | Hard | CombinatoricsProbability | ||
| Two Fives and Out | Probability | Hard | Discrete Random VariableProbability | ||
| The Price of Fandom | Probability | Easy | Continuous Random VariableProbability | ||
| The Cube's Shadow | Brainteasers | Medium | Brainteasers | ||
| Goldilocks Maximum | Probability | Easy | Continuous Random VariableProbability | ||
| Matryoshka Math | Probability | Easy | Combinatorics | ||
| Polya's Free Throws | Probability | Medium | Discrete Random VariableProbability | ||
| The Longest Short Stick | Probability | Easy | Continuous Random VariableProbability | ||
| The Five-Number Mystery | Brainteasers | Hard | BrainteasersLogic | ||
| Lucky Eight | Probability | Easy | Probability | ||
| Pocket Aces | Probability | Easy | CombinatoricsProbability | ||
| The Eight-Deck Straight | Probability | Easy | CombinatoricsProbability | ||
| Stopping with a Head Majority | Probability | Hard | Expected ValueProbability | ||
| Counting Eights | Probability | Easy | Expected ValueProbability | ||
| Beta Testing the CLT | Probability | Easy | Continuous Random VariableProbability | ||
| Roll, Flip, Repeat | Probability | Easy | Expected ValueProbability | ||
| The Ten-Door Monty Hall | Probability | Medium | Expected ValueProbability | ||
| In the Money Odds | Finance | Easy | Continuous Random VariableProbability | ||
| The Alternating Round Table | Probability | Medium | Expected ValueProbability | ||
| Sticker Shock | Brainteasers | Easy | BrainteasersCombinatorics | ||
| Early Lead | Probability | Medium | Discrete Random VariableProbability | ||
| The Power of Compounding | Brainteasers | Easy | BrainteasersCalculus | ||
| Slicing the Plane | Probability | Medium | Combinatorics | ||
| The Origin or Bust | Probability | Medium | CombinatoricsProbability | ||
| The Birthday Paradox | Probability | Medium | CombinatoricsProbability | ||
| Put-Call Parity Play | Finance | Medium | Arbitrage | ||
| The Vanishing Covariance | Statistics | Easy | ProbabilityStatistics | ||
| The Six-Bead Necklace | Probability | Easy | Combinatorics | ||
| The Dollar-Cent Swap | Brainteasers | Medium | BrainteasersLogic | ||
| Exponential Lily Pads | Brainteasers | Medium | Brainteasers | ||
| Casino War | Probability | Medium | GamesProbability | ||
| Jackpot Streak | Probability | Medium | Expected ValueProbability | ||
| The Covered Call Ceiling | Finance | Medium | Brainteasers | ||
| The Friday Boy Paradox | Probability | Medium | CombinatoricsProbability | ||
| Adjacent Dice Rolls | Probability | Medium | Markov ChainsProbability | ||
| The Josephus Circle | Brainteasers | Hard | BrainteasersGames | ||
| The Copy-Paste Regression | Statistics | Easy | Statistics | ||
| Pricing a Put Butterfly | Finance | Medium | Arbitrage | ||
| The Derangement Limit | Probability | Medium | CombinatoricsProbability | ||
| Even Sum of Primes | Probability | Easy | CombinatoricsProbability | ||
| Fair Share of the Harvest | Brainteasers | Medium | BrainteasersLogic | ||
| The Infinite Root of Six | Brainteasers | Easy | Brainteasers | ||
| Squares on a Chessboard | Brainteasers | Easy | BrainteasersCombinatorics | ||
| The Telephone Game | Probability | Medium | Markov ChainsProbability | ||
| Escaping the Origin | Probability | Medium | Markov ChainsProbability | ||
| The Change-Free Pocket | Brainteasers | Easy | BrainteasersCombinatorics | ||
| Rolling for Odds | Probability | Easy | Expected ValueProbability | ||
| To Draw or Not to Draw | Probability | Medium | Expected ValueProbability | ||
| Continuous Blackjack | Probability | Hard | GamesProbability | ||
| Biking in the Wind | Brainteasers | Easy | Brainteasers | ||
| Intertwined Brownian Motions | Probability | Easy | ProbabilityStochastic Calculus | ||
| Graph Coupon Collecting | Probability | Medium | Expected ValueProbability | ||
| Hitting the Mark | Probability | Easy | Probability | ||
| The Three-Ball Limit | Probability | Medium | Combinatorics | ||
| The King's Two-Step | Probability | Easy | Discrete Random VariableProbability | ||
| The Flat Line | Statistics | Easy | Statistics | ||
| Evenly Spaced Colors | Probability | Medium | CombinatoricsProbability | ||
| The 10-Dimensional Marble | Probability | Hard | Expected ValueProbability | ||
| The Zig-Zag Shuffle | Brainteasers | Hard | BrainteasersCombinatorics | ||
| Building Blocks | Probability | Easy | BrainteasersCombinatorics | ||
| Beta-Testing Patience | Probability | Medium | Expected ValueProbability | ||
| Put Option Anatomy | Finance | Easy | Arbitrage | ||
| Step-by-Step Subreplication | Finance | Hard | Arbitrage | ||
| The Geometric Race | Probability | Hard | Discrete Random VariableProbability | ||
| Monotonic Passcodes | Probability | Medium | Combinatorics | ||
| Pre-committed Die Rolls | Probability | Hard | Expected ValueProbability | ||
| Bankroll Battle | Probability | Easy | MartingalesProbability | ||
| Off by One | Brainteasers | Hard | BrainteasersLogic | ||
| Ferry Passengers | Brainteasers | Easy | BrainteasersLogic | ||
| Triangular Wanderer | Probability | Medium | Markov ChainsProbability | ||
| Overlapping Poisson Counts | Probability | Easy | Discrete Random VariableProbability | ||
| The Missing Product | Brainteasers | Medium | BrainteasersLogic | ||
| The Millennium Call | Finance | Medium | Probability | ||
| The Fertile Chicken | Probability | Easy | Expected ValueProbability | ||
| Summing Up OLS | Statistics | Easy | Statistics | ||
| Bitcoin Recovery | Probability | Medium | Expected ValueProbability | ||
| The Red Herring Song | Probability | Easy | Expected ValueProbability | ||
| The Twelve-Bean Riddle | Brainteasers | Hard | BrainteasersLogic | ||
| The 77 Threshold | Probability | Easy | Brainteasers | ||
| The Glass Bridge Gamble | Probability | Medium | CombinatoricsProbability | ||
| Race to the Six | Probability | Medium | Expected ValueProbability | ||
| Range vs. Midpoint | Probability | Medium | Continuous Random VariableProbability | ||
| The Dartboard Line | Probability | Hard | Continuous Random VariableProbability | ||
| Fibonacci Summation | Brainteasers | Easy | Brainteasers | ||
| Age is Just a Digit | Brainteasers | Easy | BrainteasersLogic | ||
| The Race for Heads | Probability | Medium | Discrete Random VariableProbability | ||
| Hedging the House | Finance | Easy | ArbitrageBrainteasers | ||
| Continuous Bank Arbitrage | Finance | Easy | Arbitrage | ||
| Option Value Breakdown | Finance | Easy | Brainteasers | ||
| Escaping the Boundaries | Probability | Easy | Markov ChainsProbability | ||
| The Jumping Rabbit | Probability | Easy | Combinatorics | ||
| Power-Up Pathfinding | Probability | Medium | Combinatorics | ||
| The Lucky Streak | Probability | Easy | CombinatoricsProbability | ||
| Scaling the Gamma Function | Probability | Easy | Calculus | ||
| Colony Capacity | Pure Math | Easy | Brainteasers | ||
| Brownian Ascent | Pure Math | Hard | ProbabilityStochastic Calculus | ||
| Matching Flips | Probability | Easy | Probability | ||
| Royal Stop | Probability | Hard | Expected ValueProbability | ||
| The Domino Effect | Probability | Hard | Combinatorics | ||
| Perfect Hedge | Finance | Medium | ProbabilityStatistics | ||
| Middle of the Pack | Probability | Easy | Continuous Random VariableProbability | ||
| The Stoplight Switch | Probability | Easy | Probability | ||
| Red Sock Roulette | Probability | Easy | Probability | ||
| The Triple Play Payoff | Finance | Medium | Arbitrage | ||
| The Extra Prime Roll | Probability | Easy | Discrete Random VariableProbability | ||
| The Summing Die | Probability | Medium | Discrete Random VariableProbability | ||
| Imaginary Roots | Probability | Medium | Continuous Random VariableProbability | ||
| The Handshake Problem | Brainteasers | Easy | Combinatorics | ||
| Mind Your B's and O's | Probability | Medium | Combinatorics | ||
| Big Smalls | Probability | Medium | Expected ValueProbability | ||
| The Ant's Square Escape | Probability | Hard | Expected ValueProbability | ||
| Memoryless Geometric | Probability | Easy | Discrete Random VariableProbability | ||
| Deviating from the Mean | Probability | Medium | Expected ValueProbability | ||
| The Triple Threat | Statistics | Easy | Statistics | ||
| S.O.S. on the Mediterranean | Probability | Easy | Probability | ||
| LCM Marathon | Probability | Hard | Expected ValueProbability | ||
| Stoplight Roulette | Probability | Easy | Discrete Random VariableProbability | ||
| The Unknown Shift | Probability | Hard | Expected ValueProbability | ||
| The Stopping Ratio Trap | Brainteasers | Easy | Expected ValueProbability | ||
| Sum vs. Product | Probability | Easy | CombinatoricsProbability | ||
| Strictly Ascending | Probability | Medium | CombinatoricsProbability | ||
| Bidding for Gold | Probability | Medium | Expected ValueProbability | ||
| Scissors Never Tie | Brainteasers | Easy | BrainteasersLogic | ||
| Coin on a Chessboard | Probability | Easy | BrainteasersProbability | ||
| Double the Data, Double the T-Stat? | Statistics | Easy | Statistics | ||
| The Taxman Cometh | Brainteasers | Medium | BrainteasersGames | ||
| The Generous Flipper | Brainteasers | Hard | BrainteasersGames | ||
| Opposite Ends | Probability | Easy | Expected ValueProbability | ||
| Overlapping Sums | Statistics | Medium | ProbabilityStatistics | ||
| Growing Out, Shrinking Up | Pure Math | Easy | Calculus | ||
| First to Two | Probability | Easy | GamesProbability | ||
| The Die-Hard Duel | Probability | Medium | Discrete Random VariableProbability | ||
| Equal Share | Brainteasers | Medium | BrainteasersLogic | ||
| The Lazy Parking Rush | Probability | Hard | CombinatoricsProbability | ||
| Red-Faced Rollers | Probability | Medium | Probability | ||
| Thrace River Crossing | Brainteasers | Medium | BrainteasersLogic | ||
| The Great Ball Migration | Probability | Medium | Expected ValueProbability | ||
| Meeting in the Middle | Probability | Medium | CombinatoricsProbability | ||
| Party Planning Drama | Probability | Easy | Combinatorics | ||
| Hitting the Bullseye | Probability | Medium | Probability | ||
| The Tower of Hanoi | Brainteasers | Medium | BrainteasersCombinatorics | ||
| Rowdy Root | Brainteasers | Easy | Brainteasers | ||
| The Drift Away | Probability | Medium | Markov ChainsProbability | ||
| Car Bidding | Statistics | Easy | Expected ValueProbability | ||
| Cone in a Can | Probability | Easy | Continuous Random VariableProbability | ||
| The Expanding Bubble | Pure Math | Easy | Calculus | ||
| The Cost of the Bounty | Probability | Medium | Expected ValueProbability | ||
| The Orchard Square | Brainteasers | Medium | Brainteasers | ||
| Two-Tone Towers | Probability | Medium | CombinatoricsProbability | ||
| Reverting to the Mean | Pure Math | Hard | Expected ValueStochastic Calculus | ||
| High Five Cards | Probability | Easy | Expected ValueProbability | ||
| The Gambler's Second Life | Probability | Easy | GamesProbability | ||
| Sum and Difference Correlation | Statistics | Easy | ProbabilityStatistics | ||
| Barycentric Bounds | Probability | Medium | Continuous Random VariableProbability | ||
| Late for Probability | Probability | Medium | Continuous Random VariableProbability | ||
| The Race to 200 | Brainteasers | Medium | BrainteasersGames | ||
| A Triangular Covariance | Statistics | Medium | ProbabilityStatistics | ||
| Expected Triangle Area | Probability | Easy | Expected ValueProbability | ||
| The Prep Advantage | Probability | Easy | Probability | ||
| The Last Red Cherry | Probability | Medium | CombinatoricsProbability | ||
| First to Two Heads | Probability | Medium | Markov ChainsProbability | ||
| The Missing Digit of $2^{29}$ | Brainteasers | Hard | Brainteasers | ||
| Ten Cards in a Row | Brainteasers | Medium | BrainteasersGames | ||
| Watch Your Claims | Statistics | Easy | Statistics | ||
| The Vanishing Covariance | Probability | Medium | Continuous Random VariableProbability | ||
| Thirty-Sided Difference | Probability | Easy | Expected ValueProbability | ||
| Heads Up on the Future | Statistics | Easy | Discrete Random VariableProbability | ||
| The Shifty Four | Brainteasers | Hard | BrainteasersLogic | ||
| Chords Without Crossings | Probability | Medium | CombinatoricsProbability | ||
| The Die Upgrade | Probability | Easy | Expected ValueProbability | ||
| Clean Slate | Probability | Hard | Expected ValueProbability | ||
| Counting Digits of 99^99 | Brainteasers | Medium | Brainteasers | ||
| The Consistent Kicker | Probability | Hard | Discrete Random VariableProbability | ||
| The Pairwise Tail Flip | Probability | Medium | Expected ValueProbability | ||
| Binary Multiples of 15 | Brainteasers | Easy | BrainteasersLogic | ||
| Random Polygon Crossings | Probability | Hard | Expected ValueProbability | ||
| The Forgetful Singer | Probability | Hard | Expected ValueProbability | ||
| The Truth of the Matter | Brainteasers | Medium | BrainteasersLogic | ||
| The Cycle of Guests | Probability | Hard | Expected ValueProbability | ||
| Oddly Binomial | Brainteasers | Medium | BrainteasersCombinatorics | ||
| Squaring the Matrix | Pure Math | Easy | Linear Algebra | ||
| Winning by N | Brainteasers | Easy | Markov ChainsProbability | ||
| Line of Sight | Probability | Easy | Expected ValueProbability | ||
| Cosmic Alignment | Brainteasers | Easy | Brainteasers | ||
| The Minimalist's Sock Drawer | Probability | Easy | CombinatoricsProbability | ||
| Exceeding the Logarithm | Probability | Hard | Expected ValueProbability | ||
| Gamma Moment Hunt | Probability | Easy | Continuous Random VariableProbability | ||
| Steakhouse Efficiency | Brainteasers | Easy | BrainteasersLogic | ||
| Prime Factor Showdown | Brainteasers | Hard | CombinatoricsGames | ||
| Summing Until the Ascent | Probability | Hard | Expected ValueProbability | ||
| The Forex Loophole | Finance | Easy | Arbitrage | ||
| The Adjacent Birthday Paradox | Probability | Medium | CombinatoricsProbability | ||
| Vega of a Short Call | Finance | Easy | Arbitrage | ||
| The Full House | Probability | Medium | CombinatoricsProbability | ||
| The Oracle's Coin | Probability | Medium | BrainteasersProbability | ||
| A Tale of Two Tails | Probability | Easy | CombinatoricsProbability | ||
| Chains of Five | Probability | Hard | Expected ValueProbability | ||
| The Triple Crown | Probability | Easy | CombinatoricsProbability | ||
| Summing to Twelve | Brainteasers | Medium | CombinatoricsProbability | ||
| The Zero-Strike Straddle | Finance | Medium | Continuous Random VariableProbability | ||
| The Heavy Bean | Brainteasers | Medium | BrainteasersInformation Theory | ||
| Strictly Superior | Probability | Medium | Probability | ||
| The King's Gamble | Brainteasers | Medium | BrainteasersProbability | ||
| A Game of Biased Coins | Probability | Medium | GamesProbability | ||
| The Candy Jar | Probability | Easy | Expected ValueProbability | ||
| Cracking the Safe | Brainteasers | Hard | BrainteasersCombinatorics | ||
| The Bullet Gap | Probability | Medium | BrainteasersProbability | ||
| Significant Slopes | Statistics | Hard | ProbabilityStatistics | ||
| Mixing Cherries | Probability | Medium | Probability | ||
| The Memoryless Memory Game | Probability | Medium | Expected ValueProbability | ||
| The Colorful Lineup | Probability | Easy | Combinatorics | ||
| The Power of Four | Probability | Medium | Combinatorics | ||
| The Drunk Passenger | Probability | Medium | Probability | ||
| The Final Showdown | Probability | Medium | CombinatoricsProbability | ||
| The Hidden Hue | Probability | Medium | Discrete Random VariableProbability | ||
| The Odd Prime Out | Probability | Easy | CombinatoricsProbability | ||
| The Fibonacci Fraction | Brainteasers | Medium | CalculusCombinatorics | ||
| Odd Grid Sums | Probability | Medium | CombinatoricsProbability | ||
| Square Edge Roulette | Probability | Easy | Probability | ||
| The Ultimate Holiday Policy | Probability | Medium | Expected ValueProbability | ||
| The Token Tug-of-War | Probability | Hard | GamesProbability | ||
| Powers of Brownian Motion | Pure Math | Easy | MartingalesStochastic Calculus | ||
| Scaling the Regression | Statistics | Easy | Statistics | ||
| The Unattainable Stamp | Brainteasers | Easy | BrainteasersCombinatorics | ||
| The Infinite Wait | Probability | Hard | Discrete Random VariableProbability | ||
| The Clueless Audience Member | Probability | Medium | BrainteasersProbability | ||
| The Index-Digit Match | Brainteasers | Medium | Expected ValueProbability | ||
| The Third Ace | Probability | Hard | Discrete Random VariableProbability | ||
| The Great Sheep Heist | Brainteasers | Easy | BrainteasersLogic | ||
| The Triple Constraint | Probability | Easy | Combinatorics | ||
| Trapping the Center | Probability | Hard | Continuous Random VariableProbability | ||
| Double Flip Destiny | Probability | Easy | GamesProbability | ||
| The Great Ant Crossing | Brainteasers | Easy | BrainteasersCombinatorics | ||
| Tracing the Exponential | Pure Math | Medium | Linear Algebra | ||
| The Three-Roll Gamble | Probability | Medium | Expected ValueProbability | ||
| The Biased Coin Test | Statistics | Easy | ProbabilityStatistics | ||
| The Rap Shuffle | Probability | Easy | CombinatoricsProbability | ||
| The Election Arbitrage | Finance | Medium | ArbitrageProbability | ||
| The Run Around | Probability | Hard | Expected ValueProbability | ||
| The Geometric Square | Brainteasers | Hard | BrainteasersLogic | ||
| The Banker's Square Deal | Probability | Medium | GamesProbability | ||
| Slicing the Tuna | Probability | Medium | Continuous Random VariableProbability | ||
| The Multiset Match | Probability | Medium | CombinatoricsProbability | ||
| The Half-Cycle Limit | Probability | Hard | Expected ValueProbability | ||
| The Cashier's Dilemma | Probability | Hard | CombinatoricsProbability | ||
| Mall Spending Habits | Statistics | Hard | Statistics | ||
| The Mouse Massacre | Brainteasers | Hard | Brainteasers | ||
| Vowel Play | Brainteasers | Easy | Brainteasers | ||
| Summing Deviations | Probability | Easy | Probability | ||
| Colorful Chains | Probability | Medium | Expected ValueProbability | ||
| The Lily Pad Race | Brainteasers | Easy | BrainteasersLogic | ||
| The Survival Game | Probability | Medium | Discrete Random VariableProbability | ||
| The Power of Log | Pure Math | Medium | Calculus | ||
| The Neighborly Glove Problem | Probability | Hard | CombinatoricsProbability | ||
| The Zero-Risk Mix | Finance | Medium | Expected ValueStatistics | ||
| Alternating Aisles | Brainteasers | Easy | CombinatoricsProbability | ||
| Leveling the Flipping Field | Probability | Medium | GamesProbability | ||
| The Centered Coin | Brainteasers | Easy | BrainteasersGames | ||
| Group Separation | Probability | Easy | Probability | ||
| The Optimal Penny Stack | Brainteasers | Medium | BrainteasersCombinatorics | ||
| The Race for Two Sides | Probability | Easy | GamesProbability | ||
| The Correlation Triangle | Probability | Medium | ProbabilityStatistics | ||
| The Product of Heads and Tails | Probability | Easy | Expected ValueProbability | ||
| The Candy Box Gambit | Probability | Easy | Probability | ||
| A Normal Imbalance | Probability | Easy | Continuous Random VariableProbability | ||
| The Handshake Count | Brainteasers | Easy | BrainteasersCombinatorics | ||
| The Normalizing Constant | Statistics | Medium | Expected ValueStatistics | ||
| The Arena of Attrition | Probability | Hard | GamesProbability | ||
| The Tip of the Cone | Probability | Easy | Continuous Random VariableProbability | ||
| Odds Before Evens | Probability | Easy | CombinatoricsProbability | ||
| Labeling the Cube | Probability | Medium | Combinatorics | ||
| Unique Pairwise Sums | Brainteasers | Medium | BrainteasersCombinatorics | ||
| The Long Walk to Ruin | Probability | Hard | Discrete Random VariableProbability | ||
| The Node Collector | Probability | Medium | Expected ValueProbability | ||
| The Three-Legged Table | Probability | Hard | BrainteasersProbability | ||
| Dodecagon Color Clash | Probability | Medium | CombinatoricsProbability | ||
| Segment Intersection | Probability | Medium | CombinatoricsProbability | ||
| Backwards Ball Drawing | Probability | Easy | Probability | ||
| Leo's Last-Minute Dash | Probability | Medium | Continuous Random VariableProbability |
