UKMT Grey Kangaroo, 2022

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

There are five big trees and three paths in a park. It has been decided to plant a sixth tree so that there are the same number of trees on either side of each path. In which region of the park should the sixth tree be planted?

(A) $A$ (B) $B$ (C) $C$ (D) $D$ (E) $E$

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