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UKMT Junior Kangaroo, 2016

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

The lengths of three adjacent sides of a quadrilateral are equal. The angle between the first and second of these sides is $60^\circ$ and the angle between the second and third of these sides is $100^\circ$ . What is the largest angle of the quadrilateral?

(A) $130^\circ$ (B) $140^\circ$ (C) $145^\circ$ (D) $150^\circ$ (E) $160^\circ$

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