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Problem 367

Geometry Difficulty 2.0 Prove it UKMT Junior Mathematical Olympiad · United Kingdom · 2016

Linda has a very thin sheet of paper measuring 20 cm by 30 cm. She repeatedly folds her paper in half by folding along the shorter line of symmetry. She finishes when she has a rectangle with area $75\text{ cm}^2$ . What is the perimeter of her final rectangle?

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Source: UK Mathematics Trust, licensed © UK Mathematics Trust; past papers published free at ukmt.org.uk. Statement reproduced verbatim; metadata (topic, difficulty, ordering) added by this project. Solutions are the publisher's, linked not copied.