Skip to content
Math Gym
Addition Guide

Addition Level 28: 4d + 4d (overflow). large answer-window addition.

1. Fill thousands

Step 1: Fill thousands
raw windows
running strip
Thousands window: 4 + 6 = 10. Hold raw 10; carry settles later.

2. Fill hundreds

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

3. Fill tens

Step 3: Fill tens
raw windows
running strip
Tens window: 8 + 4 = 12. Hold raw 12; settle carry later.

4. Fill ones

Step 4: Fill ones
raw windows
running strip
Ones window: 6 + 7 = 13. Hold raw 13; settle carry later.

5. Settle carry

Step 5: Settle carryKeep ones; carry moves left.raw windows
settled digits
Settle raw 10 | 12 | 12 | 13 into 11333; keep ones and move carry left.