I have the Robert Kaufman "Quilter's Little Helper" on my phone and use it frequently for quilty calculations. Math and I have never been friends. I would recommend it if you can get it. (It is free)
Just plugged in your measurements : Robert Kaufman says you need 266 inches of binding. This includes 10 inches "margin". Calls for a 30 inch square of fabric to make your bias binding.
Last edited by suern3; 07-14-2019 at 01:11 PM.