Explain how you can compare the cost of two items that are different sizes.

Compare the cost for the each (smallest) unit.

Step-by-step 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

First find the unit price for each. Then compare the unit prices. The item that has the lesser unit cost is the better buy.  

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