A pycnometer of volume \( 500 \, \text{cm}^3 \) was used in specific gravity test and following data is observed. Weight of dry empty pycnometer = \( 125 \, \text{g} \), weight of dry soil and pycnometer = \( 500 \, \text{g} \), weight of dry soil and distilled water filled in pycnometer up to top = \( 850 \, \text{g} \). Then the specific gravity of soil solids is