Maths Olympiad Prep

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, 2024

Geometry Difficulty 1.2 Junior Find the answer Canada

Square PQRSPQRS is divided into
1616 smaller congruent squares, as
shown.

What fraction of PQRSPQRS is
shaded?

Pick one

Solution

Square PQRSPQRS is made up of
1616 equal-sized small squares.

Of these, 22 are fully shaded and
88 are half-shaded.

This shading is equivalent to fully shading 2+812=2+4=62 + 8 \cdot \frac{1}{2} = 2 + 4 = 6 of
the 1616 small squares.

Thus, square PQRSPQRS is 616=38\frac{6}{16} = \frac{3}{8} shaded.

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.