Although $\displaystyle{4}<{5}\usepackage{cmbright}\Huge\$ , you must find a common denominator to compare fractions. Finding a common denominator, you can compare $\displaystyle\frac{{52}}{{117}}\usepackage{cmbright}\Huge\$ to $\displaystyle\frac{{45}}{{117}}\usepackage{cmbright}\Huge\$ and see that $\displaystyle\frac{{52}}{{117}}>\frac{{45}}{{117}}\usepackage{cmbright}\Huge\$ , which means $\displaystyle\frac{{4}}{{9}}>\frac{{5}}{{13}}\usepackage{cmbright}\Huge\$ . The correct answer is $\displaystyle\frac{{4}}{{6}}>\frac{{4}}{{9}}\usepackage{cmbright}\Huge\$ .