639 US customary cups in dry gallons

Conversion formula
How to convert 639 US customary cups to dry gallons?

We know (by definition) that: $1\mathrm{uscup}\approx 0.0537104379609565\mathrm{drygallon}$

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 ⁢ uscup ≈ 34.3209698570512 ⁢ drygallon

Conversion in the opposite direction

The inverse of the conversion factor is that 1 dry gallon is equal to 0.0291367057564241 times 639 US customary cups.

It can also be expressed as: 639 US customary cups is equal to $\frac{1}{\mathrm{0.0291367057564241}}$ dry gallons.

Approximation

An approximate numerical result would be: six hundred and thirty-nine US customary cups is about thirty-four point three two dry gallons, or alternatively, a dry gallon is about zero point zero three times six hundred and thirty-nine US customary cups.