The average density of living matter on earthâs land areas is 0.10 g/cm2 . what mass of living matter in kilograms would occupy an area of 0.125 ha?

Density is a value for mass, such as kg, divided by a value for volume or area. Density is a physical property of a substance that represents the mass of a certain substance per unit volume or unit area. From the problem statement, we are given the density of the living matter in a particular area and the area. To calculate mass, we simply multiply the area to the density. However, we should remember that the units should be homogeneous or the same and if not, we convert.

Mass = density x area
Mass = 0.10 g / cm^2 (0.125 ha) ( 1x10^8 cm^2 / 1 ha )
Mass = 1250000 g or 1250 kg