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UKMT Junior Kangaroo, 2021

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

The diagram shows three triangles which are formed by the five line segments $ACDF$ , $BCG$ , $GDE$ , $AB$ and $EF$ so that $AC = BC = CD = GD = DF = EF$ . Also $\angle CAB = \angle EFD$ . What is the size, in degrees, of $\angle CAB$ ?

(A) $40$ (B) $45$ (C) $50$ (D) $55$ (E) $60$

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