Question
Milk and water are in the ratio 3:4. After adding 9 litres
of milk and 8 litres of water, the ratio becomes 5:6. Find the initial quantity of the mixture.Solution
Let the initial quantity of milk and water be '3y' and '4y' litres respectively.
So, (3y + 9):(4y + 8) = 5:6
Or, 6 × (3y + 9) = 5 × (4y + 8)
Or, 18y + 54 = 20y + 40
Or, 2y = 14
Or, y = 7
Therefore, required quantity = 3y + 4y = 7y = 7 × 7 = 49 litres
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