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When I answer questions on Math SE, I generally like to leave long, detailed answers that tie up all of the loose ends on the problem. Because of this, combined with the fact that I am a slower typer than some, it often happens that just as I am finishing up my answer, somebody else posts an answer saying pretty much the exact same thing as the answer than I am about to post.
When I find myself in this dilemma, it is hard to decide whether or not I should post my answer. If I post an answer that says the same thing (if perhaps a bit more thoroughly) it will seem that I am copying the other user's answer. When this happens, should I just delete what I have written so far and more on? Should I edit and add to the other user's answer? Or should I post mine alongside the other?