Correct. Subtract 4 from both sides and then multiply both sides by 3:

$\displaystyle\frac{{1}}{{3}}{y}+{4}-{4}={16}-{4}\usepackage{cmbright}\Huge\$ , so $\displaystyle\frac{{1}}{{3}}{y}={12}\usepackage{cmbright}\Huge\$ . Then $\displaystyle{3}\cdot\frac{{1}}{{3}}{y}={3}\cdot{12}\usepackage{cmbright}\Huge\$ , so $\displaystyle{y}={36}\usepackage{cmbright}\Huge\$ .