To find the volume of the object, subtract initial volume from final volume:

801 ml-600 ml= 201 ml

Divide the mass of the object by its mass:

$$\frac{482.63\ g}{201\ ml}$$

the density is $$\frac{482.63\ g}{201\ ml}=2.41315\ \frac{g}{ml}$$

round answer to the correct number of significant digits (3).

$$2.41315\ \frac{g}{ml}\ =\ 2.41\frac{g}{ml}$$