Number of rectangles to cover a circle After searching around I found this is similiar to the Gauss Circle but different enough (for me anyway) that it doesn't translate well.
I have a circle, radius of 9 that I need to completely cover with rectangles 4 x 8. What is the minimum number of whole rectangles required.
My own calculations concluded it's between 8 and 11. I found this by setting the maximum number of panels equal to (diameter of circle / panel height)x(diameter of circle/panel width) to obtain 10.125 rounded up to 11 
I do think I could safely use 10 due to waste.
I then found the minimum by setting the number of panels equal to (area of circle/area of panel). This gave me an answer of 7.95, rounded up to 8.
Is there a better way to do this?

I was also unable to cover with fewer than 12. Were it allowed to cut two of the rectangles lengthwise into a couple of $2\times8$ rectangles each, then 10 would suffice.

