For Beatrix's latest art installation,
she has fixed a 2 x 2 square sheet of steel to a wall.
She has two 1 x 2 magnetic tiles, both which she
attaches to the steel sheet, in any orientation, so
that none of the sheet is visible and the line
separating the two tiles cannot be seen. As shown
alongside, one tile has one black cell and one grey
cell; the other tile has one black cell and one spotted
cell.
How many different looking 2 x 2 installations can
Beatrix obtain?

there are 2 combinations given already, and a 1 x 2 tile is half of the steel square, so you could also have black+black and grey+spots so add all combinations together and you get 4 combos!

: )

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