15 US dry barrels in US gallons
Result
The conversion result is: 15 US dry barrels is equivalent to 458.181818181818 US gallons.[1]
Conversion formula
How to convert 15 US dry barrels to US gallons?
We know (by definition) that: 1 drybarrel ≈ 30.5454545454545 usgallon.
We can set up a proportion to solve for the number of US gallons.
1 drybarrel / 15 drybarrel ≈ 30.5454545454545 usgallon / x usgallon
Now, we cross multiply to solve for our unknown x:
x usgallon ≈ (15 drybarrel / 1 drybarrel) * 30.5454545454545 usgallon → x usgallon ≈ 458.1818181818175 usgallon
Conclusion:
15 drybarrel ≈ 458.1818181818175 usgallon

Conversion in the opposite direction
The inverse of the conversion factor is that 1 US gallon is equal to 0.00218253968253968 times 15 US dry barrels.
It can also be expressed as: 15 US dry barrels is equal to 1 / 0.00218253968253968 US gallons.
Approximation
An approximate numerical result would be: fifteen US dry barrels is about four hundred and fifty-eight point one eight US gallons, or alternatively, a US gallon is about zero times fifteen US dry barrels.
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.