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UKMT Junior Kangaroo, 2021

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Using only pieces like the one shown in the diagram, Zara wants to make a complete square without gaps or overlaps. What is the smallest number of pieces she can use?

(A) $5$ (B) $8$ (C) $16$ (D) $20$ (E) $75$

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