If you increase the mass but leave the volume the same what happens to the density of the object

Density is a property of an object or substance that can be described through the correlation of the mass of an object over its volume.

Mathematically, density = mass / volume.
In description, the relationship of density and mass is positively correlated and with volume, inversely.
Since density and mass is positively correlated then if you increase the mass, the density of the object will also increase leaving density and volume the same.

Example:
Mass = 10 g changes to 20
Volume = 5 cm3
Density =?

1. D = m / v
2. D = 10 g / 5 cm3
3. D = 2 g / cm3
4. D = 20 g / 5 cm3
5. D = 4g/cm3