A barrel contains a mixture of alcohol and water in the ratio 7:4 respectively. If 12 litres of water are added to it, the ratio of alcohol to water becomes 7:6. Find the initial total quantity of the mixture in the barrel,
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Correct answer: D
Explanation
The correct answer is option 4 i.e. 66 litres.
Let alcohol = 7k and Water = 4k
7k/(4k + 12) = 7/6
⇒ 42k = 28k + 84
⇒ 14k = 84
⇒ k = 6
Initial total = 7k + 4k = 11k = 11 × 6 = 66 litres