I figure it like Pam did. The 5 inch becomes a 4 1/2 inch finished. So using 3 of the 4 1/2 squares equals 13 1/2. Ea. block is then 13 1/2 X 13 1/2. Multiply that (13 1/2) times however many blocks wide you want to get the desired width of your quilt & the same for the length. Hope this helps?