A chemist mixes one liter of pure water with x liters of a 60% salt solution, and the resulting mixture is a 10% salt solution. What is the value of x? Select the correct option:
A) 1 / 5  B) 1 / 3  C) 1 / 2  D) 1  E) 3

Rationale: "concentration of salt in pure solution = 0 concentration of salt in salt solution = 60 % concentration of salt in the mixed solution = 10 % the pure solution and the salt solution is mixed in the ratio of - - > ( 60 - 10 ) / ( 10 - 0 ) = 5 / 1 1 / x = 5 / 1 x = 1 / 5 answer : a"
Answer: A