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VTMO 2026 - Grade 9 - Semifinal - SET 07 - Self-study Question 2

VTMO · VTMO 2026 - Grade 9 - Semifinal - SET 07 - Self-study

Question 2

The first box has 4 blue and 6 red balls of one size. The second has 8 blue and 2 red balls, all larger than those in the first box. Choose $m$ balls from the first box and $n$ from the second to guarantee two of the same color but different sizes. Minimize $m+n$.
  1. 6
  2. 7
  3. 8
  4. 9
  5. 10