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UKMT Junior Kangaroo, 2026

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

Rafael uses three squares to create a shape. The first has side-length 3 cm. The second has side-length 5 cm and one of its vertices is placed in the centre of the first square. The third square has side-length 7 cm and one of its vertices is placed in the centre of the second square, as shown in the diagram. The top edges of all three squares are parallel. What is the total shaded area in $\text{cm}^2$ ?

(A) $66$ (B) $74.5$ (C) $75$ (D) $77.5$ (E) $83$

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