138 imperial gallons in US gallons
Result
The conversion result is: 138 imperial gallons is equivalent to 165.73108971967 US gallons.[1]
Conversion formula
How to convert 138 imperial gallons to US gallons?
We know (by definition) that: 1 imperialgallon ≈ 1.20094992550486 usgallon.
We can set up a proportion to solve for the number of US gallons.
1 imperialgallon / 138 imperialgallon ≈ 1.20094992550486 usgallon / x usgallon
Now, we cross multiply to solve for our unknown x:
x usgallon ≈ (138 imperialgallon / 1 imperialgallon) * 1.20094992550486 usgallon → x usgallon ≈ 165.73108971967068 usgallon
Conclusion:
138 imperialgallon ≈ 165.73108971967068 usgallon
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Conversion in the opposite direction
The inverse of the conversion factor is that 1 US gallon is equal to 0.00603387090310861 times 138 imperial gallons.
It can also be expressed as: 138 imperial gallons is equal to 1 / 0.00603387090310861 US gallons.
Approximation
An approximate numerical result would be: one hundred and thirty-eight imperial gallons is about one hundred and sixty-five point seven two US gallons, or alternatively, a US gallon is about zero point zero one times one hundred and thirty-eight imperial gallons.
Footnotes
[1] The precision is 15 significant digits (fourteen digits to the right of the decimal point).
Results may contain small errors due to the use of floating point arithmetic.