The mass of a piece of paper is 0.02 g and the mass of a solid substance and the piece of paper is 20.036 g. If the volume of the solid is 2.16 cm3, calculate the density of the substance up to proper number of significant digits.

Mass of piece of paper - 0.02 gMass of solid substance and piece of paper - 20.036 g.'. Mass of solid substance : 20.0360.02020.016or :20.02 (up to second decimal place)Volume of solid - 2.16 cm3 Density = Mass  Volume =20.022.16=9.268Since 2.16 has 3 significant figures, the answer should also contain 3 significant figures..'. Density up to proper number of significant figures : 9.27 glcm3.'