If the tank is then field to capacity how many half-gallon bottles how many cords will it make?

Divide 12 by 4 first to figure out how many gallons are in each 1/4 of the tank.

12/4=3

So if I added another 1/4 to the capacity:

It could hold 15 gallons.

All you have to do to find how many half bottles can be filled is to times 15 by two since we are filling half gallon bottles.

15x2=30

30 bottles.