Hard Trader Interview Questions
Everything asked of traders, filtered to the hard end - useful for calibrating where you actually are.
40 questions, 28 of them free to practise right now. The topics that come up most are probability (26), expected value (13), brainteasers (11), combinatorics (11).
- A coin thick enough to land on its sideHardProbabilityBrainteasersView →
- A small sub-triangleHardProbabilityRandom VariablesView →
- A three-way race to the first headHardProbabilityRandom VariablesView →
- A triangle of consecutive integersHardBrainteasersView →
- Expected chord between two random pointsHardProbabilityExpected ValueView →
- Expected chord intersectionsHardProbabilityCombinatoricsView →
- Expected largest of ten ballsHardCombinatoricsExpected ValueView →
- Expected local maxima in a shuffleHardProbabilityExpected ValueView →
- Guessing cards from a known pileHardProbabilityExpected ValueView →
- HTH before HHTHardProbabilityRandom VariablesView →
- Loops from tying noodlesHardProbabilityExpected ValueView →
- More coins, more heads?HardProbabilityCombinatoricsView →
- One of each face before the two of heartsHardProbabilityCombinatoricsView →
- Pairs left in the drawerHardCombinatoricsExpected ValueView →
- Pirate gameHardMarket Making & Betting GamesView →
- Rolling until two rolls are closeHardProbabilityExpected ValueView →
- Rounds to see all faces with two diceHardProbabilityExpected ValueView →
- Runs of red and blue marblesHardCombinatoricsExpected ValueView →
- Shortest of three piecesHardProbabilityRandom VariablesView →
- Six pieces, none past a halfHardProbabilityRandom VariablesView →
- Smallest card sharing a boxHardProbabilityExpected ValueView →
- The boy born on a TuesdayHardProbabilityConditional Probability & ExpectationView →
- The drunk passengerHardProbabilityConditional Probability & ExpectationView →
- The reroll advantage in a die duelHardProbabilityMarket Making & Betting GamesView →
- Twelve balls, one oddHardBrainteasersView →
- Two random segments overlappingHardProbabilityRandom VariablesView →
- Weighings for the odd beanHardBrainteasersView →
- Will the three-legged table stand?HardProbabilityView →
- Ages from product and sumHardCombinatoricsBrainteasers Premium
- Best-of-seven underdogHardProbabilityRandom Variables Premium
- Blue-eyed islandersHardBrainteasers Premium
- Bluffing frequency in pokerHardProbabilityExpected Value Premium
- Counting two-pair handsHardProbabilityCombinatorics Premium
- Defective stack of coinsHardCombinatoricsBrainteasers Premium
- Deriving the first-price shading factorHardProbabilityExpected Value Premium
- Handshakes at a dinner partyHardCombinatoricsBrainteasers Premium
- Hats in a lineHardBrainteasers Premium
- Prisoners and the light switchHardBrainteasers Premium
- The all-pay auctionHardProbabilityExpected Value Premium
- The racing camelsHardBrainteasers Premium
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