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UKMT Pink Kangaroo, 2026

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Fifteen points are equally spaced around a circle. How many regular polygons can be drawn by selecting the vertices of each polygon from these points?

(A) $5$ (B) $7$ (C) $9$ (D) $11$ (E) $13$

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