Hi all........yesterday i asked a question about the size of a block. I got some good info from the wonderful people on this board. I am starting a quilt. Pic. is attached. One block is a 16 piece block using 3 in. squares. The next block is a 10 1/2 inch solid white block......however the four corners have a half square triangle in the corners. How do i achieve this? thanks in advance. hugs cheryl