Quote Originally Posted by Aussiebear View Post
Respectfully I have to disagree. The first of the half circles is half the radius of the Quadrant and the second is much less.
As far as I can tell, the larger half circle size is determined by the quadrant radius - nothing else.
The smaller half circle , if it's to fit by just touching the larger half circle and its top being at the top of the vertical leg of the quadrant, has a diameter about (exactly?) 2/3rds the diameter of the larger half circle. So the linear proportions remain the same regardless of scale, so all areas are in proportion to the square of the linear dimensions.
The function I gave gives the same results as your calculations; have you compared?