Question

set up the equation, relating the new ratio of salt to solution to the desired 20% salt solution. 19.2/(160 - x)=20/100 (160 - x)/19.2 = 20/100 0/19.2 = x/160 19.2/x = 20/100

Explanation:

Step1: Understand percentage - ratio relationship

A 20% salt - solution means the ratio of salt to the total solution is $\frac{20}{100}$. Let's assume we start with a certain amount of salt and solution, and we are making some change (here subtracting $x$ from the solution amount). If the amount of salt is 19.2 and the new amount of the solution is $160 - x$, the ratio of salt to the new - solution is $\frac{19.2}{160 - x}$. This ratio should be equal to the desired 20% or $\frac{20}{100}$.

Answer:

A. $19.2/(160 - x)=20/100$