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, 2017

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Alex colours all the small squares that lie on the two longest diagonals of a square grid. She colours $2017$ small squares. What is the size of the square grid?

(A) $1009 \times 1009$ (B) $1008 \times 1008$ (C) $2017 \times 2017$ (D) $2016 \times 2016$ (E) $2015 \times 2015$

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