Diagonal touch
Weekly Problem 21 - 2012
Two rectangles are drawn in a rectangle. What fraction of the rectangle is shaded?
Two rectangles are drawn in a rectangle. What fraction of the rectangle is shaded?
Problem
Image
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What fraction of rectangle $PQRS$ is shaded?
Student Solutions
Image
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$\frac{16}{81}$ is shaded.
Let $x$ and $y$ be the distances shown. Then the shaded area is $8y + x$. But there are a number of similar triangles and from one pair