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UKMT Junior Kangaroo, 2026

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Julia has four different coloured pencils and wants to use some or all of them to colour the map of four regions shown in the diagram. She wants to ensure that two regions that share a common border are shaded in different colours. In how many different ways can she colour the map?

(A) $12$ (B) $18$ (C) $24$ (D) $36$ (E) $48$

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