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UKMT Junior Mathematical Challenge, 2022

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

The diagram shows a seven-sided polygon, PQRSTUVPQRSTUV. It is formed from two equilateral triangles PQWPQW and STUSTU of side-length 5 cm and 8 cm respectively. The two triangles overlap in an equilateral triangle of side-length 2 cm. What is the perimeter of PQRSTUVPQRSTUV?

(A) 27 cm27\text{ cm} (B) 30 cm30\text{ cm} (C) 33 cm33\text{ cm} (D) 36 cm36\text{ cm} (E) 39 cm39\text{ cm}

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