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A floor is covered by a tessellation of equilateral triangles, each having three equal arcs inside it. What proportion of the area of the tessellation is shaded?

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Bull's Eye

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Blue and White

Age 11 to 14 Challenge Level:

In the examples below identical squares of side one unit contain some circles shaded blue.

In which of the four examples is the shaded area greatest?


This problem is also available in French: Bleu et Blanc