Answer
Final mass = 37.2g + 62.7g = 99.9 g
Final temperature = $20^{\circ}C$
Final density = 11.35 g/$cm^{3}$
Work Step by Step
Mass is an extensive property. It depends on the amount of matter while temperature and density are intensive properties which only depend on the type of matter, not the amount of it. Here, temperature and density are the same at the initial and final stage because both of the two mixed substances are of the same temperature and density.