Question
In a mixture containing a certain quantity of pure
alcohol, 20% of the alcohol is removed from the container and replaced with an equal amount of water. Subsequently, 25% of the mixture is withdrawn and replaced with the same quantity of water. Determine the ratio of alcohol to water in the resulting mixture.Solution
ATQ, Let, the initial quantity of pure alcohol be 'a' litres. Quantity of alcohol in the resultant mixture = a × 0.80 × 0.75 = 0.6a litres Quantity of water in the resultant mixture = a - 0.6a = 0.4a litres So the desired ratio = 0.6a: 0.4a = 3:2
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