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UKMT Senior Mathematical Challenge, 2017

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

In the diagram, all the angles marked $\bullet$ are equal in size to the angle marked $x°$ . What is the value of $x$ ?

(A) $100$ (B) $105$ (C) $110$ (D) $115$ (E) $120$

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