Math Insight

Every row, column, and box in a completed Sudoku sums to 45 — the sum of digits 1 through 9. This is a useful sanity check.

Math Insight
✓ Completed! 👍
8
5
4
2
1
3
4
2
5
6
9
2
9
1
3
2
6
5
9
7
1
6
5
8
2
8
7
1
6
5
4
3
5
1
2
5
2
1
6
8
4
1
4
9
2
3
Math Insight

Every row, column, and box in a completed Sudoku sums to 45 — the sum of digits 1 through 9. This is a useful sanity check.

Math Insight