UKMT Grey Kangaroo, 2015

Geometry Difficulty 1.0 Junior Find the answer United Kingdom

A triangle has sides of lengths $6$ cm, $10$ cm and $11$ cm. An equilateral triangle has the same perimeter. What is the length of the sides of the equilateral triangle?

(A) $18$ cm (B) $11$ cm (C) $10$ cm (D) $9$ cm (E) $6$ cm

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