You can put this solution on YOUR website! How many fluid ounces in a gallon?
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Use z for the # of ounces in a gallon.
Which is cheaper -1 gallon for $12.50 or 84 fluid ounces for $22?
1250/z = Cents per ounce for 1 gallon
2200/84 = cents per ounce for 84
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The smaller # is less expensive.