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Addition

Level 23 / realistic untimed

4d + 3d (overflow)

5 visual steps / large answer-window addition

1. Fill thousands

Step 1: Fill thousands
raw windows
running strip
Thousands window: 4 + 0 = 4. Hold 4; wait for carry from the next window.

Thousands window: 4 + 0 = 4. Hold 4; wait for carry from the next window.

2. Fill hundreds

Step 2: Fill hundreds
raw windows
running strip
Hundreds window: 7 + 6 = 13. Hold raw 13; settle carry later.

Hundreds window: 7 + 6 = 13. Hold raw 13; settle carry later.

3. Fill tens

Step 3: Fill tens
raw windows
running strip
Tens window: 8 + 5 = 13. Hold raw 13; settle carry later.

Tens window: 8 + 5 = 13. Hold raw 13; settle carry later.

4. Fill ones

Step 4: Fill ones
raw windows
running strip
Ones window: 6 + 4 = 10. Hold raw 10; settle carry later.

Ones window: 6 + 4 = 10. Hold raw 10; settle carry later.

5. Settle carry

Step 5: Settle carry
Settle onceKeep ones; carry moves left.raw windows
settled digits
Settle raw 4 | 13 | 13 | 10 into 5440; keep ones and move carry left.

Settle raw 4 | 13 | 13 | 10 into 5440; keep ones and move carry left.

Practice Level 23

A few quick rounds make digit release automatic; carry is the only thing to keep.

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