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, 2023

Geometry Difficulty 2.4 Junior Find the answer Canada

In the diagram, $PQR$ is a line segment, $\$\angle$ PQS =
$125\degree$ $,$ $\angle QSR=x\degree$ $, and$ SQ=SR $.$ x$?

Pick one

Solution

Of the 100 small identical squares, 28 are presently unshaded,
and so $100-28=72$ are shaded. So that 75% of the area of $WXYZ$ is shaded, 75 of the 100 small squares must be shaded. Therefore, $75-72=3$ more of the
small squares must be shaded.

Figure for this problem

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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.