Ice at 0 deg. Celsius?

ice at 0 deg. celsius is placed in a styro-foam cup containing 320 g of lemonade at 27 deg celsius. the specific heat capacity of lemonade is virtually the same as that of water; that is Cw=4186 J/kg deg. celsius. after the ice and lemonade reach an equilibrium temperature, some ice still remains. the latent heat of fusion for water is LF=3.35 x10^5 J/kg. determine the m of ice that has melted.