A cube of ice is floating in a liquid of relative density 1.25 contained in a beaker. When the ice melts, the level of the liquid in the beaker

The density of the liquid is $\mathrm{\rho }=1.25 \mathrm{g}{ \mathrm{cm}}^{-3}$, which is higher than the density of water which is $1.0 \mathrm{g}{ \mathrm{cm}}^{-3}$. This means that for $\mathrm{x}$ grams of ice, the volume of the liquid displaced is $\frac{\mathrm{x}}{\mathrm{\rho }}={\mathrm{x}}^{\text{'}}$ (say). But $\mathrm{x}$ grams of ice, on melting, will produce $\mathrm{x}{ \mathrm{cm}}^3$ of water. Since $\mathrm{x}>{\mathrm{x}}^{\text{'}}$, the level of liquid will rise. The volume of the liquid displaced by ice cube is less than the volume of the water formed when ice melts.