Food for Thought

"If you want to be happy, be." — Leo Tolstoy

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

Set theory provides the formal foundation for Sudoku's rules: each digit must appear exactly once per set.

Math Insight