Some ethylene glycol, HOCH2CH2OH, is added to your car's cooling system along with 4.4 kg of water. If the freezing point of the water-glycol solution is -15.0°C, how many grams of HOCH2CH2OH must have been added?

I used the equation: 15 celcius = 1 x 1.86 celcius/moles per kg x molality and got 8.064 but I don't know the units and I don't know where to use 4.4kg of water.