As I figure
start with 2520 take away 20 to stagger seams so we have 2500. then half is 1250, half 625 half 312.5 half 156 so half is 78 Ok so we agree that far.
We also agree would be 64 wide.
So how about using just enough to make it 64 wide so we just take 64 and double it the 5 times. we have 64 then 128 then 256 then 512 then 1024 then 2048 inches. So sew 49 strips together. and take off 10 inches in order to stagger seams. Then you could use the other 11 stripes to make one of your borders around the strips in the middle.
you will need 13 inches of border strips on all sides and voila your quilt will be 90 X 90.
Now someone please check my math to make sure I am right befor she starts. If she chooses to do it this way.
Are Batiks 42.25 inches wide? If not it would throw our numbers off a little but we have got to be close.