## Problem. Magic
Square (click here to see the problem statement)

__My Solution__
(21 in Center).

###

### If 21 is to be the number in the center
square, we can assume that the sum of each row, column, and diagonal
is the product of 21 and 3: That is the AVERAGE value of the squares
is 21. This establishes a target sum of 63. The sum of the remaining
pairs must equat 63 - 21 = 42.

### I make a list of 20 pairs:

**1, 41** |
**2, 40** |
**3, 39** |
**4, 38** |
**5, 37** |

**6, 36** |
**7, 35** |
**8, 34** |
**9, 33** |
**10, 32** |

**11, 31** |
**12, 30** |
**13, 29** |
**14, 28** |
**15, 27** |

**16, 26** |
**17, 25** |
**18, 24** |
**19, 23** |
**20, 22** |

### Here are several solutions I found. {I have no doubt there
are many others. A good question would be - How solutions are
there? But this will have to wait for another day}:

###

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