Hi Elaine,
I'm wondering who set you up with this assignment. If squares are cut 2 5/8" the block will finish at 5 7/8".
Or, if they are cut at 2 3/4" the block finishes at 6 1/4". Maybe my brain is filled with sawdust and the math ain't mathing anymore.
But I wouldn't mind being a mouse in your pocket at the next committee meeting....