What quantity of water should taken out to concentrate 18 liters of 40% acidic liquid to 60% acidic liquid?	Choices: A) 5 liters B) 10 liters C) 15 liters D) 8 liters E) 6 liters

Rationale: "required answer is = 18 ( 60 - 40 ) / 60 = 6 liters answer is e"
Answer: E