A regular octagon is coloured as shown. What fraction of its area is red?
The circus tent

A regular octagon is coloured as shown. What fraction of its area is red?
A cone has height 6 and base diameter 6. On it lie two points, one exactly halfway up, the other diametrically opposed at the base. What’s the shortest distance between these points going along the cone surface?
A square and two rectangles, connected by two circular arcs, form a square. What is the proportion of the orange to the green area?
Two circles of area π and 9π respectively are contained in a parallelogram. What’s its area?
Two congruent pyramids placed at different distances from the observer appear as equilateral triangles in a square frame. If the closest one is at 100 meter, how far is the distant pyramid?
A square is fitted into an equilateral triangle as shown. What fraction is shaded?
In a circle, two congruent chords are connected in a point. A line segment is drawn through the circle center as shown, forming two angles. What is the proportion α : β?
Two circles are embedded in a frame of size 9 x 8. What is their total area?
Two isosceles triangles are placed as shown. What is the proportion of the line segments a and b?
In a square, an interior point is drawn with an angle to the top vertices of 120°. What’s the angle between the chords formed by the two arcs centered in these vertices?