To find the unit price for each size divide the cost of each package by the corresponding weight.
Size 1
[tex]\frac{3.68}{11.3}=0.32[/tex]The unit price is $0.32/ounce
Size 2
[tex]\frac{8.98}{29.3}=0.31[/tex]The unit price is $0.31/ounce
Size 2 is better to buy because it has a cheaper unit size, it means you can buy more ounces with the same amount of money if you buy size 2.