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UKMT Senior Mathematical Challenge, 2025

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

The diagram shows an equilateral triangle divided into nine smaller equilateral triangles, with two additional lines. What fraction of the large triangle is shaded?

(A) $\frac{1}{3}$ (B) $\frac{1}{4}$ (C) $\frac{3}{8}$ (D) $\frac{2}{9}$ (E) $\frac{4}{9}$

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