The problem is: I should calculate the mass of a 3cm cube of aluminium. Previously, there was a question saying: A 2cm cube of aluminium has mass 21.6g. Calculate the density of aluminium in g/cm<cubed> and so I think that it is associated with the question I am asking.. but I don't know how should I calculate the mass, if I don't know the density??
Dear Marky It's said that cube is made of alumunium. If no more details are given then normal conditions are meant. Corresponding value of density for aluminium can be found in tables, for example here