About this pathway
Brainteasers tests how you reason when you have no direct formula. Top trading firms use these to evaluate raw problem-solving ability, creative decomposition, and how you communicate structured thinking under pressure. This pathway covers every major category used in real interviews.
Who it's for
All quant candidates — brainteasers appear at virtually every top trading firm regardless of role. Especially common in first-round screens at Jane Street, Optiver, and similar firms.
Skills covered
Course modules
Example problems
A taste of what you'll work through.
100 doors, all closed. Pass k: toggle every kth door. Which doors are open at the end?
Two trains 120 miles apart approach at 60 mph each. A fly bounces at 120 mph. How far does it travel?
How many piano tuners are there in Chicago? Walk through your estimation process.
Expected outcome
You will develop a pattern library of brainteaser archetypes, internalize structured decomposition, and practice articulating reasoning clearly — exactly what interviewers at top firms want to see.