Question
A mixture contains milk and water in the ratio 7:5. If 6
liters of water is added to the mixture, the ratio of milk to water becomes 7:6. Find the original quantity of water in the mixture.Solution
Let the quantity of milk and water initially be 7x and 5x, respectively. After adding 6 liters of water, the ratio becomes 7:6, so 7x / (5x + 6) = 7/6. Cross-multiplying: 6 × 7x = 7 × (5x + 6) 42x = 35x + 42 7x = 42 x = 6 Original quantity of water = 5x = 5 × 6 = 30 liters. Answer: c) 30 liters
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