Shannon Conroy, age 17 of Johnson City, Tenn., for her question:

IN MATHEMATICS, WHAT IS A MAGIC SQUARE?

A magic square in mathematics is an array of distinct numbers so arranged in a square that the sums of each row, each column and each main diagonal are equal.

For example, here is magic square of order three (the order is the number of horizontal rows or vertical columns), that produces the constant sum of 15:

2    7     6

9    5     1

4    3     8

In ancient times such configurations of numbers were thought to be good luck charms or tallismans. Later, mathematicians became interested in the magic square as a problem in mathematical analysis.

Here is a magic square of order four that produces the constant

    sum of 34:

1    8    10    15

12    13    3    6

7    2    16    9

14    11    5    4