Answer:
The 12-pound bag of dog food.
Explanation:
To find out which is the better buy you start by divinging 10.80 by 12 and then you divide 10.20 by 8 and you get .90 cents for the 12 pound while you get 1.275 dollars. Which means the 12 pound bag is the better by because it is less money per pound than the 8 pound bag.