306/6 is 51 is you add one to one side and take away the other the six numbers become: 46, 48, 50, 52, 54, 56 as you added one to one side substituting the other you took away from, therefore the smallest would be 46.
6000 - 1800 = 4200
4200/4 = 1050
so she donated 25% to charity
3x to the third=180
third root 3x to the third =third root180