A rectangle with given side lengths is folded back and forth such that the corner touches the opposite side as shown. What is the minimal shaded fraction?
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A rectangle with given side lengths is folded back and forth such that the corner touches the opposite side as shown. What is the minimal shaded fraction?
A triangle with an inscribed triangle. What fraction of the former does the latter cover in terms of lengths a, b, c, d, e and f?
A square with several line segments. What fraction is green?
A square containing an isosceles triangle with given side lengths. What fraction is red?
A square containing four smaller squares. What fraction of its area is orange?
A triangle with side lengths a and b and an inscribed rhombus. What is the blue fraction in terms of a and b?
A semicircle, a circle, a square and an equilateral triangle. The two points are the tangency point and the semicircle centre. What fraction of the total area is yellow?
A circle with an inscribed triangle with an inscribed circle. The centre of the large circle is on the small one. What fraction of the area is blue?
Three congruent squares inscribed in a rectangle. What fraction of the total area is green?
A cyclic quadrilateral and two diagonals. What fraction of its area is blue?