Initial quantity of milk = 60 litres When 12 liters of milk taken out from it and replaced by water, then quantity of milk = $$60-12=48$$ litres and water = $$12$$ litres (Total mixture still remains 60 litres) Again, 12 litres of mixture is taken out, => Fraction of mixture taken out = $$frac{12}{60}=frac{1}{5}^{th}$$ => Milk left = $$48-(frac{1}{5} imes48)=38.4$$ litres => Water left = $$60-38.4=21.6$$ litres $$ herefore$$ Required ratio = $$frac{38.4}{21.6}=frac{64}{36}=16:9$$ => Ans - (D)