Because ounces and gallons are both standard systems of measurement, they convert between each other with no hassle and always come out even. Thus, there are exactly 128 fluid ounces
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1 gallon = 128 fluid ounces.
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There are 128 fluid ounces in 1 gallon. Hope that helps!
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1.5 US gallons is equivalent to 192 US fluid ounces. To convert gallons to ounces, simply multiply the amount of gallons to 128 ounces.
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