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Brain Teasers Interview Questions
Brain teasers test structured thinking under pressure — logic puzzles, invariants and clever counting that interviewers use to see how you reason, not just what you have memorised. All 20 brain teasers questions below come with a full worked solution — sign in to check your answers and track your progress.
Read the guide: Quant Brain Teasers: The Puzzles Interviewers Actually Ask
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Screwy Pirates
Jane StreetOptiver
Trailing Zeros in 100!
Goldman SachsJ.P. Morgan
Two Eggs, 100 Floors
GoogleGoldman Sachs
Horse Race — Top 3
GoogleTwo Sigma
Clock Hands at 3:15
Morgan StanleyBarclays
Sum 1 to 100
Jane StreetGoldman Sachs
100 Lockers
GoogleTwo Sigma
Poisoned Wine
GoogleJane Street
Last Digit of 2^100
Goldman SachsMorgan Stanley
Mislabeled Jars
Jane StreetOptiver
Burning Ropes — 45 Minutes
Goldman SachsMorgan Stanley
12 Balls, One Odd
CitadelJane StreetTwo Sigma
Handshakes at a Party
Goldman Sachs
Bridge Crossing
GoogleJane Street
Ants on a Triangle
Goldman SachsOptiver
Water Jugs
Google
Three Switches
Goldman SachsMorgan Stanley
The Camel and the Bananas
Jane StreetGoogle
The Blue-Eyed Islanders
Jane StreetTwo Sigma
The Mutilated Chessboard
GoogleHRT
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