Compound Inequalities Word Probems - Examples & Practice

Your professor only gives two midterms and a final. The semester average is calculated by taking $\frac{1}{3}$ of the average of the mid-term scores and $\frac{2}{3}$ of the final exam score. If Hayley scores a $56$ and a $64$ on the two mid-terms, what is the minimum score must she earn on the final to get a grade of C or above?