15 dry quarts in dry gallons
Result
The conversion result is: 15 dry quarts is equivalent to 3.75 dry gallons.[1]
Conversion formula
How to convert 15 dry quarts to dry gallons?
We know (by definition) that: 1 dryquart ≈ 0.25 drygallon.
We can set up a proportion to solve for the number of dry gallons.
1 dryquart / 15 dryquart ≈ 0.25 drygallon / x drygallon
Now, we cross multiply to solve for our unknown x:
x drygallon ≈ (15 dryquart / 1 dryquart) * 0.25 drygallon → x drygallon ≈ 3.75 drygallon
Conclusion:
15 dryquart ≈ 3.75 drygallon

Conversion in the opposite direction
The inverse of the conversion factor is that 1 dry gallon is equal to 0.266666666666667 times 15 dry quarts.
It can also be expressed as: 15 dry quarts is equal to 1 / 0.266666666666667 dry gallons.
Approximation
An approximate numerical result would be: fifteen dry quarts is about zero dry gallons, or alternatively, a dry gallon is about zero point two seven times fifteen dry 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.