Answer:
Multiply the number of cans by the volume of each: 12,000 oz.
Explanation:
You find the total volume of more than one can by adding the volumes of the cans involved.
For 2 cans, the volume would be ...
12 oz + 12 oz = 24 oz
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When you consider adding numbers more than a couple of times, you start looking for ways to simplify the effort. Multiplication was invented for that purpose. Here, multiplying the volume of 1 can by 1000 is the same as adding the volumes of 1000 cans.
For 1000 cans with volume of 12 oz each, the volume of the total is ...
1000 × 12 oz = 12,000 oz.