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UKMT Junior Kangaroo, 2018

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

The diagram shows a triangle joined to a square to form an irregular pentagon. The triangle has the same perimeter as the square. What is the ratio of the perimeter of the pentagon to the perimeter of the square?

(A) $2:1$ (B) $3:2$ (C) $4:3$ (D) $5:4$ (E) $6:5$

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