What is in the second glass?

If you have a bottle of Coca Cola and if you share (from that bottle) in one glass 51%, in second 38% and in the third 11%, isn’t in every glass the same Coca Cola?
In 1913 Macedonia was shared too. 51% took Greece, 38% Serbia and 11% Bulgaria. Only the part that took Serbia now is independent country Macedonia. But the Greeks still call us fyrom, which is insulting, and are saying that only thay have a right to use the word Macedonia.