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Math Gym
Addition Guide

Addition Level 19: 3d + 3d (any). answer-window addition.

1. Fill hundreds

Step 1: Fill hundreds
raw windows
running strip
Hundreds window: 7 + 4 = 11. Hold raw 11; carry settles later.

2. Fill tens

Step 2: Fill tens
raw windows
running strip
Tens window: 2 + 8 = 10. Hold raw 10; settle carry later.

3. Fill ones

Step 3: Fill ones
raw windows
running strip
Ones window: 9 + 6 = 15. Hold raw 15; settle carry later.

4. Settle carry

Step 4: Settle carryKeep ones; carry moves left.raw windows
settled digits
Settle raw 11 | 10 | 15 into 1215; keep ones and move carry left.