Question

Find the relative density of copper block of mass 216g having volume of 80cm3 (density of water= 1g/cm3)

Answer 1

Absolute density = 216/80=2.7gm/cm3
Relative density =absolute density /water density
=2.7/1=2.7 ans

Answer 2

According to question

Mass of Copper Block = 216 gm

Also Volume of block = 80 Cm^3

Thus Absolute density  = Mass / Volume  = 218 / 80
                                                                   = 27.25 gm/Cm^3

And Thus 
Relative density = Absolute Density/ Density of Water = 27.25 / 1
                                                                                      = 27.25