Answer:
256 fl oz
Step-by-step explanation:
1 gallon is 128 fluid ounces. So, 2 gallons is 2×128 = 256 fluid ounces.
Noelle bought 256 ounces of lemonade.
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Comment on the problem
In order to give a numerical answer, we have assumed the problem statement to be "... bought two gallon cartons ...". This is a precise quantity.
The wording here indicates the purchase of an unknown number of two-gallon cartons. Each such carton would hold 256 fluid ounces, but it doesn't say how many Noelle bought.
