A crystalline salt on being rendered anhydrous loses 45.6% of its weight

A crystalline salt on being rendered anhydrous loses 45.6% of its weight. The percentage composition of the anhydrous salt is Aluminium = 10.50%, Potassium = 15.1% Sulphur = 24.96%, Oxygen = 49.925. Find the simplest formula of the anhydrous and crystalline salt.