What fraction of this square region is shaded? Stripes are equal in width, and the figure is drawn to scale.

Source: Julia Robinson Mathematics Festival

**SOLUTION**

**
**Suppose without loss of generality that the width of the stripes equals 1 unit.

Draw a grid as shown in the above figure.

Area of shaded stripe equals square units.

Area of shaded stripe equals square units.

Area of shaded stripe equals square units.

Total area of shaded stripes square units.

Area of square region = square units.

Shaded stripes’ fraction of this square region = .

**Answer**: .

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