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UKMT Pink Kangaroo, 2025

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Prem wants to place the digits 1 to 8, inclusive, in the eight cells of the diagram. He wants to place one digit in each cell so that any two cells that contain consecutive digits are not adjacent (including diagonally). What digits could be placed in the shaded cell?

(A) $1$ or $8$ (B) $2$ or $7$ (C) $3$ or $6$ (D) $4$ or $5$ (E) $7$ or $8$

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