<span>Volume Percent (volume/volume%) is defined to be the ratio of the volume of solute to the volume of solution times 100%.
The acetic acid is the solute volume. The bottle of vinegar is the solution volume.
Acetic acid (28.2ml) / Vinegar(165ml) x 100% = 17.1%</span>
If they're different sizes and densities, you are able to separate the substances.