UKMT Grey Kangaroo, 2016

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

A $3$ cm wide strip is grey on one side and white on the other. Maria folds the strip, so that it fits inside a rectangle of length $27$ cm, as shown. The grey trapeziums are identical. What is the length of the original strip?

(A) $36$ cm (B) $48$ cm (C) $54$ cm (D) $57$ cm (E) $81$ cm

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