Question
A 210 litres mixture contains only water and phenyl in
the ratio 3:4, respectively. If 70 litres of this mixture is replaced with 25 litres of alcohol, then what will be the ratio of quantity of water to that of alcohol in the resultant mixture?Solution
Initial quantity of water in the mixture = 210 × (3/7) = 90 litres After removing 70 litres of the mixture, quantity of water = (210 – 70) × (3/7) = 140 × (3/7) = 60 litres Therefore required ratio = 60:25 = 12:5
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