Here is how they work together. Three 7" blocks = two 10.5" blocks. Four 10.5" blocks = three 14" blocks. This is like a modular quilt and these are all multiples of 3.5". I love math, sorry if I lost some of you. I don't have a clue how I'm going to put this together yet. If I knew that I would be bored with it and wouldn't want to finish it. As it is, there are more blocks to be made and fun playing on the design wall.