## Elementary Algebra

Let X represent the amount of salt in the resulting solution. Since the first solution is 20 gallons\ and the second solution is 30 gallons, the resulting solution will be 20 + 30 = 50 gallons. To find X, the amount of salt in the resulting solution, we use the following guideline: Amount of salt in the first solution + amount of salt in the second solution = Amount of salt in the final solution. 20% $\times$ 20 + 25% $\times$ 30 = X $.2 \times 20 + .25 \times 30 =X$ 4 + 7.5 = X X = 11.5 There are 11.5 gallons of salt in the 50 gallons solution. Since we need to calculate the percentage of salt, we proceed: $\frac{11.5}{50}$ $\times$ 100% = 23%