stamps are n large sheets w/perforations n between. how many different ways can u buy 4 attached square stamp

Question

two ways to put them together are considered the same if one way can be turned or flipped so that its outline looks like the other way

Answer 1

There are four non-congruent ways. If you were allowed to consider congruence (i.e turning and flipping), another 11 possibilities occur. But for your question, it is four.