More magic!
It is known that a magic square consists of a grid filled in with the digits 1-9 such that every column, row, and diagonal add up to the same constant (typically 15), as shown at right:
How many ways, though, can this be accomplished, including rotations and reflections?
The image shows one of the ways.
Image credit: https://www.w3resource.com
The answer is 8.
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1 solution
The top left number can be chosen in 4 ways. (Any of the even numbers)
Once chosen, the bottom left number can be chosen in 2 ways.
After that, the rest of the numbers fall nicely into place.
This gives 4 ⋅ 2 = 8 ways.
Actually, this boils down to only one way, which can be reflected about either a diagonal and/or rotated to form the other 7.