sustraley, 1" strips all the way around your quilt. Measure and make sure your center measures 21 1/2". You really only need 3/4" strips but I think it would be easier to sew 1" and trim. 3 into 21 = 7 units per side and 9 units for the top and bottom. Had you gone with a 4 1/2" rectangle it would have fit with no strip added, 4 into 20= 5 units per side. If you want a wider strip you'll have to go to 2 1/2" and your center will measure 24 1/2"which then you'll need 8 units per side and 10 top and bottom. Brat was right on the 1 1/2" but you have to remember to divide that in half because your sewing that strip on each side....or you could just sew on 1 side and 1 top or bottom and go modernistic
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