Skip to content / Đến nội dung
ThichHocToan.com

IMC 2024 Grade 8 — Selection round Question 2

IMC · IMC 2024 Grade 8 — Selection round

Question 2

The four central squares of an $8\times8$ chessboard are removed as shown. What is the largest number of queens that can be placed on the remaining $60$ squares so that no two attack each other? A queen attacks the nearest piece in any common row, column, or diagonal. For this question, removed squares cannot hold queens but do not block attack lines.

Question illustration
  1. $6$
  2. $8$
  3. $9$
  4. $10$
  5. $12$