Wt. in air = 0.25 N Wt.in water = 0.15 N Therefore, lost in wt. in water = Upthrust in water = 0.25 - 0.15 = 0.10 N. Wt. in paraffin oil = 0.17 N. .. loss in wt. in oil = upthrust in the oil = 0.25 - 0.17 = 0.08 Ratio of upthrust in oil to upthrust in water = \(\frac{0.08}{0.10}\) = \(\frac{8}{10}\) = \(\frac{4}{5}\) Or 4 : 5