Jane Street

Interview Question

Quant Trader Intern Interview
Jane Street

You and an opponent are each given a number uniformly at random between 0 and 1. The player with the higher number wins 1 point from the other. After seeing your own number (but not your opponent's), you can choose to offer 'double' odds or just continue. If you offer double, your opponent, having seen their own number, can either reject the offer (losing 1) or accept it. If they accept, the winner takes 2 points from the loser according to who has the higher number. What is the optimal strategy for playing this game?

Unlock the Full Solution

Enter your email to get instant access to the complete solution, explanation, and similar practice problems.

Insights on 100+ quant firms, understand where to apply, and maximize your chances.

Get the official 2025 QB Quant Firm Tier List

Check your email inbox — you should get the interview in 1-2 minutes!