In a 3×3 magic square using 1 to 9, every row, column and diagonal sums to the same number. What number must be in the center?
Hint: Find the magic sum first.
5.
1 to 9 add up to 45, so each row sums to 15. The four lines through the center count it four times, which forces the center to be 5.
More Math Puzzles and Number Brain Teasers