Addition Level 9: 2d + 2d (any). answer-window addition. 1. Fill tens79 + 68Step 1: Fill tens79plus6813raw windows7 + 6 = 13 then keep 3; carry waitsrunning strip13Tens window: 7 + 6 = 13. Hold raw 13; carry settles later.2. Fill onesStep 2: Fill ones79plus681317raw windows9 + 8 = 17 then keep 7; carry waitsrunning strip137Ones window: 9 + 8 = 17. Hold raw 17; settle carry later.3. Settle carryStep 3: Settle carryKeep ones; carry moves left.raw windows13 | 17settled digits1 | 4 | 7answer 147Settle raw 13 | 17 into 147; keep ones and move carry left.
