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UKMT Junior Mathematical Challenge, 2024

Geometry Difficulty 1.0 Junior Find the answer United Kingdom

A hexagon is formed by arranging three equilateral triangles, as shown in the diagram. The side-length of the largest equilateral triangle is 10 cm. What is the perimeter, in cm, of the hexagon?

(A) $45$ (B) $40$ (C) $35$ (D) $30$ (E) more information needed

Figure for this problem

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