a chemist mixes one liter of pure water with x liters of a 30 % salt solution , and the resulting mixture is a 20 % salt solution . what is the value of x ?
"concentration of salt in pure solution = 0 concentration of salt in salt solution = 30 % concentration of salt in the mixed solution = 20 % the pure solution and the salt solution is mixed in the ratio of - - > ( 30 - 20 ) / ( 20 - 0 ) = 1 / 2 1 / x = 1 / 2 x = 2 answer : e"
divide(20, subtract(30, 20))