A square contains three squares (black sides), one of which has an extended side (blue). What is the proportion yellow : blue?
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Solution
Yellow : blue is 1 : 1.

Poem
Squares and rectangles
A part of his spirituality
Abstract forms far from reality
Interaction of rythm and lines
In order to create universal beauty
The primary colours are Mondrian’s vocabulary
Always rooted on nature formly
Dreaming of past and majesty
Painting for poetry
