Originally Posted by
yngldy
Take the size you want and divide by 12.5. 6.5 divided by 12.5 = 52% 8.5=68% make a copy of the diagram for the quilt at 52 or 68% (you might have to add seam allowances) and you will have the sizes needed for the pieces.
Correction of wording: Take size you want, and divide by size you have, that will give you the % that you need to reduce/enlarge. Small number divided by large number gives the %.