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Stage: 3 Short Challenge Level: 
See all short problems arranged by curriculum topic in the short problems collection
In this magic square, which uses all whole numbers from $7$ to $15$ inclusive, each of the rows, columns and the two main diagonals has the same total.
Which number replaces $n$ in the completed square?
If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.
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NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.