The specific gravity of a substance is given by G = DS/DW, where DS is the density

Question:

The specific gravity of a substance is given by G = DS/DW, where DS is the density of the substance in kg/m3 and DW is the density of water, which is known to be 1000 kg/m3. The density of a particular substance is measured to be DS = 500 ± 5 kg/m3. Estimate the specific gravity, and find the uncertainty in the estimate.