639 dry quarts in dry gallons

Conversion formula
How to convert 639 dry quarts to dry gallons?

We know (by definition) that: $1\mathrm{dryquart}\approx 0.25\mathrm{drygallon}$

We can set up a proportion to solve for the number of dry gallons.

Now, we cross multiply to solve for our unknown $x$:

Conclusion: 639 ⁢ dryquart ≈ 159.75 ⁢ drygallon

Conversion in the opposite direction

The inverse of the conversion factor is that 1 dry gallon is equal to 0.00625978090766823 times 639 dry quarts.

It can also be expressed as: 639 dry quarts is equal to $\frac{1}{\mathrm{0.00625978090766823}}$ dry gallons.

Approximation

An approximate numerical result would be: six hundred and thirty-nine dry quarts is about zero dry gallons, or alternatively, a dry gallon is about zero point zero one times six hundred and thirty-nine dry quarts.