I was talking mainly about the simple case presented above. x*y can be 0 (mod 6) but I don't think it takes knowing abstract algebra and a deep knowledge of mo

I was talking mainly about the simple case presented above. x*y can be 0 (mod 6) but I don't think it takes knowing abstract algebra and a deep knowledge of modulo and axioms to figure that out. I hope math teachers that don't know abstract algebra know that!