If we go into the standard U.S measurement system, then we see that 128-fluid ounce equals a gallon. Simply, 7.57 ounce of bottle equals a gallon.

In US, A gallon has 128 fluid ounce. In simple word, 7.57 ounce of bottles in a US gallons.

128 fluid ounces = 1 US gallon

It is 1/128 the liquid ounce in a gallon, it means 128/16.9 = 7.57 bottles.

7.57 bottles have 16.9 ounce of water in each. And that is exactly equal to 1 US gallon.

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