72 US quarts in US gallons
Result
The conversion result is: 72 US quarts is equivalent to 18 US gallons.[1]
Conversion formula
How to convert 72 US quarts to US gallons?
We know (by definition) that: 1 usquart ≈ 0.25 usgallon.
We can set up a proportion to solve for the number of US gallons.
1 usquart / 72 usquart ≈ 0.25 usgallon / x usgallon
Now, we cross multiply to solve for our unknown x:
x usgallon ≈ (72 usquart / 1 usquart) * 0.25 usgallon → x usgallon ≈ 18.0 usgallon
Conclusion:
72 usquart ≈ 18.0 usgallon

Conversion in the opposite direction
The inverse of the conversion factor is that 1 US gallon is equal to 0.0555555555555556 times 72 US quarts.
It can also be expressed as: 72 US quarts is equal to 1 / 0.0555555555555556 US gallons.
Approximation
An approximate numerical result would be: seventy-two US quarts is about zero US gallons, or alternatively, a US gallon is about zero point zero six times seventy-two US quarts.
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.