A 60 litre container holds a mixture of milk and water in the ratio 7:3. If 12 litres of this mixture is taken out and replaced with 12 litres of pure milk, what is the new ratio of milk to water?
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Correct answer: A
Explanation
Given:
Total mixture = 60 liters
Milk : Water = 7 : 3
Mixture taken out = 12 liters
Pure milk added = 12 liters
Total ratio = 7 + 3 = 10
Milk = (7/10) × 60 = 42 liters
Water = (3/10) × 60 = 18 liters
Of the 12 liters taken out
Milk = (7/10) × 12 = 8.4 liters
Water = (3/10) × 12 = 3.6 liters
Remaining milk = 42 − 8.4 = 33.6 liters
Remaining water = 18 − 3.6 = 14.4 liters
After adding 12 liters of pure milk
Milk = 33.6 + 12 = 45.6 liters
Water = 14.4 liters
New ratio = 45.6 : 14.4
New ratio = 19 : 6