Answer:
Compare the cost for the each (smallest) unit.
Explanation:
You can calculate the cost per unit
For example :
20 ounces of water of brand A cost 1.50
30 ounces of water of brand A cost 2
20 ounces of water cost 1.50/20 = 0.075 dollar per ounce
30 ounces of water cost 2/30 = 0.0677 dollar per ounce
Explanation: