Squares Level 5: 3d center stack mastery (raw >= 30). center-window pre-training. 1. Locate center stackCenter window of 864 times 8641. Locate center stackUse every digit pair whose positions meet in the middle.864times8648x82 pairs3 pairs2 pairs4x4Active multiplication train windowcenter windowUse every digit pair whose positions meet in the middle.2. Add highlighted pairs2. Add highlighted pairs864times8648x82 pairs3 pairs1002 pairs4x4Active multiplication train windowcenter window totalcenter -> 1008 x 4 + 6 x 6 + 4 x 8 = 100.3. Read center total3. Read center totalCenter window answerCenter window = 100.
