You would divide 43 by 4.
43/4 is 10, with the remainder of 3. Each person would get 10 water bottles and she would keep three to herself because we want to split them equally. Now, if people wanted to split the 3 water bottles left to, then they would have 10.75 water bottles...but that is not the case. Also, if the little girl includes herself, then they would each get 8 water bottles and 3 water bottles remaining. If they wanted the remaining, they would get 8.6 water bottles. Anyway...just wanted to put those facts out there. Hope this helped!