Solved UPSC CDS/OTA Question
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Q · Ratio and ProportionMedium · 45s
In a milk shop there are three varieties of milk, ‘Pure’, ‘Cure’ and ‘Lure’. The ‘Pure’ milk has 100% concentration of milk. ‘The ratio of milk to water in the ‘Cure’ is 2: 5 and in the Lure it is 3: 8 respectively. Sonali purchased 14 litres of Cure and 22 litres of Lure milk and mixed them. If she wanted to make the concentration of milk in the mixture of purchased milk to 50%. How many litres of ‘Pure’ milk is she needed?
TopicRatio and Proportion
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Ratio of milk and water in ‘cure’ milk
= 2 : 5
Ratio of milk and water in ‘cure’ milk
= 3 : 8
Quantity of milk in ‘cure’ milk
Final Answer: Option B — 8 litres