In a mixture of milk and water, there is only 26% water. After replacing the mixture with 7 liters of pure milk , the percentage of milk in the mixture become 76%. The quantity of mixture is:

• A. None of these
• B. 91 liters
• C. 65 liters
• D. 38 liters

Answer: (B)

         Milk             Water           74%             26%        (initially)           76%             24%        ( after replacement)      Left amount = Initial amount  1 - r e p l a c e d   a m o u n t t o t a l   a m o u n t      24  = 26 1 - 7 k => k = 91