A square array of numbers, usually positive integers, is called a magic square if the sums of the numbers in each row, each column, and both main diagonals are the same. The summation of the first row gives 42 , hence the summation of each row, column and diagonals should be 42. 13+12+17=42 12+F+16=42 F+12+16=42 F+28=42 F=42−28 F=14