In a Mixture, the ratio of Milk and Water is 7: 5. If

Solution

Let the Initial quantity of Mixture be= 12x Total mixture after 12 litre of mixture drawn off = (12x-12) According to question, Quantity of Milk = (12x-12) × 7/12 Quantity of Water = (12x-12) × 5/12 After adding 8 litre water,  Quantity of water in Mixture = (12x-12) × 5/12+ 8 Ratio of Milk and water after replacing = 1 : 1 ((12x-12) × 7/12)/((12x-12)× 5/12+ 8) = 1/1 (12x-12)×  7/12 = (12x-12) × 5/12 + 8 (84x-84)/12 = (60x-60)/12 + 8 84x-84=60x-60+96  x=5  So total Mixture = 12x = 12 × 5 = 60 litre Total milk in Initial Mixture = 60/12 × 7 = 35 litre