Jane Street–styleAnalystQuantitative AnalystQuestion #609
There are 30 blue balls and 30 red balls, and two urns. Your opponent may arrange the balls in the two urns in any way he chooses, without telling you the arrangement. You then select one urn and draw a ball at random from it. You win $10 if you draw a blue ball, and $0 otherwise. How much should you be willing to pay to play this game?
Build Your Approach
State the assumptions, try a simple case, then work toward a general solution. Check the result and explain how it changes if an assumption changes.
Try the free diagnostic with worked solutions →Get Free Interview Prep Resources
More Jane Street–Style Analyst Questions
You are given two identical eggs and a 100-story building. Your task is to determine the highest floor from which you can drop an egg without it breaking.How can you invert a pyramid of coins by moving only three coins?You flip a fair coin repeatedly and stop flipping after three heads in a row occur. What is the expected number of flips required?How many handshakes occur if every person in a room shakes hands with every other person exactly once?Given that the probability it rains on Sunday is 40% and the probability it rains on the weekend (Saturday or Sunday) is 60%, what is the probability it rains on Saturday?
Practice the Reasoning Behind the Answer
Bring your target roles and interview timeline to a free quant consult. Discuss your preparation priorities and how Quant Blueprint’s lessons, practice and mock interviews can help.
Book a Free Quant ConsultYour goals · your preparation · your next steps