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Math Gym
Addition Guide

Addition Level 20: 3d + 3d (mastery). answer-window addition.

1. Fill hundreds

Step 1: Fill hundreds
raw windows
running strip
Hundreds window: 8 + 6 = 14. Hold raw 14; carry settles later.

2. Fill tens

Step 2: Fill tens
raw windows
running strip
Tens window: 7 + 5 = 12. Hold raw 12; settle carry later.

3. Fill ones

Step 3: Fill ones
raw windows
running strip
Ones window: 5 + 9 = 14. Hold raw 14; settle carry later.

4. Settle carry

Step 4: Settle carryKeep ones; carry moves left.raw windows
settled digits
Settle raw 14 | 12 | 14 into 1534; keep ones and move carry left.