A regular hexagon is folded back and forth along the dotted line. What fraction of the area is yellow?
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Solution
The yellow fraction is 11/16.

It is easily seen that the dotted line cuts the sides on 3/4. One can then dissect the figure in equilateral triangles of side 1/4 as shown. It is now a matter of counting 66 yellow triangles on a total of 96.
Poem
Bobline haircut for a fighting lady
Like Joan of Arc, the Virgin, the heroe
She was fighting for France
For freedom with her lance
And steel on her hair
To go anywhere
The young lady
Coming from Domremy
Giving France liberty
She left to save her country
An angel holly !
