Civil Service Exam Reviewer · Word Problems · hard
How many liters of water must be added to 100 liters of a 70% alcohol solution to reduce it to 20% alcohol?
- 71.43 liters
- 250 liters
- 28.57 liters
- 50 liters
Answer
B. 250 liters
Solution
Alcohol stays 70 L. 70 = 0.2(100 + x) → x = 250 L.
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