8 problems, 60 seconds each. Answer as a decimal or fraction (e.g. 0.25 or 1/4). Within 1.5% counts. Speed and streaks pay.

Five hidden d6. The contract settles at their sum. Each round you see one more die, then quote a two-sided market. Some counterparties see every die. Others are noise. Quote too wide and you're rejected; quote carelessly and the informed ones pick you off.

10 questions. Give a range you're 90% sure contains the true answer. Narrow ranges score more, but a miss scores zero. A calibrated trader hits about 9 of 10. Scientific notation like 3e8 works.

10 problems: arithmetic, sequences, probability. 100 points per correct answer, plus a speed bonus of up to 300 for finishing inside 5 minutes. One shot per problem, one run per day.

3 minutes. Problems step up a tier every 5 solves. Answers lock in when correct. Enter on a wrong answer, or Skip, costs a life. Three strikes and you're out. Rush never touches anything but your best score.

One question for everyone today. Give a range you're sure contains the answer. If it does, you score by how much tighter it is than everyone else's correct ranges. A miss scores zero. Scientific notation like 3e8 works.