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, coloumn and diagonals should be 42. 13+12+17=42 13+E+11=42 E+13+11=42 E+24=42 E=42−24 E=18 17+10+G=42 G+17+10=42 G+27=42 G=42−27 G=15 E+G=18+15 E+G=33