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Multiplication

Level 27 / mastery

4d x 4d (small)

6 visual steps / multi-digit window train

1. Left Edge

1. Left Edge
 raw windows
2x3 = 6. Raw fits.

2x3 = 6. Raw fits.

2. 2-Pair Window

2. 2-Pair Window
 raw windows
2 pairs: 2x1 + 1x3 = 5. Raw fits.

2 pairs: 2x1 + 1x3 = 5. Raw fits.

3. 3-Pair Window

3. 3-Pair Window
 raw windows
3 pairs: 2x2 + 1x1 + 3x3 = 14. Carry waits for settle.

3 pairs: 2x2 + 1x1 + 3x3 = 14. Carry waits for settle.

4. 4-Pair Center

4. 4-Pair Center
 raw windows
4 pairs = 10. Carry waits for settle.

4 pairs = 10. Carry waits for settle.

5. 3-Pair Right Window

5. 3-Pair Right Window
 raw windows
3 pairs: 1x1 + 3x2 + 1x1 = 8. Raw fits.

3 pairs: 1x1 + 3x2 + 1x1 = 8. Raw fits.

6. Settle strip

6. Settle strip
Settle onceRaw windows keep ones; extra carry moves left.raw windows
settled strip
6 | 5 | 14 | 10 | 8 | 5 | 1 -> 6650851.

6 | 5 | 14 | 10 | 8 | 5 | 1 -> 6650851.

Practice Level 27

A few quick rounds make the train automatic; each raw window keeps one digit.

Start Level