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IMC 2010 — Keystage 3 (IWYMIC) — team Question 4

xIMC · IMC 2010 — Keystage 3 (IWYMIC) — team

Question 4

Sixty-four dots form an $8\times8$ array with adjacent same-row or same-column dots one centimetre apart. Count all rectangles of area twelve square centimetres whose vertices are among the dots.