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UKMT Grey Kangaroo, 2020

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

Bella took a square piece of paper and folded two of its sides to lie along the diagonal, as shown, to obtain a quadrilateral. What is the largest size of an angle in that quadrilateral?

(A) $112.5^\circ$ (B) $120^\circ$ (C) $125^\circ$ (D) $135^\circ$ (E) $150^\circ$

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