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🇷🇺 Russia VsOSh AI 2026, School Stage (Sirius platform, region group 2), grades 9–11
Forecasting Ball Colours
Expected correct predictions when always guessing the less likely colour.
- Statement
- Russian · Read it in English (Google Translate)
- To hand in
- Written answers
- Data type
- 📈 Time series, ✍️ Written questions
- Estimated difficulty
- ★☆☆☆☆
- Solution
- See a solution ↗ · best opened after you have tried
Get ready on the platform
The chapters of the learning path that prepare for this problem.
These chapters are picked from the solution: showing them may hint at the approach.
›How to tackle it
- Read everything first. Note what each question asks and how it is marked.
- Work on paper. Justify every step: at an olympiad, the reasoning earns the points.
- Then compare. Open the solution only once you have an answer, and compare your reasoning with it.
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