If you multiply all sides of a three-dimensional object with the same factor $k$, then the following is true:
the enlargement factor for each length is $k$;
the enlargement factor for each surface is ${k}^{2}$;
the enlargement factor for the volume is ${k}^{3}$.
When you have two objects with the same shape, then one object can be derived from the other by multiplying with such a fixed enlargement factor (or reduction factor).