Rate equals work done over time, or $\displaystyle{r}=\frac{{W}}{{t}}\usepackage{cmbright}\Huge\$ . Henry's rate for the previous job was $\displaystyle\frac{{400}}{{2}}\usepackage{cmbright}\Huge\$ square feet per hour. His rate for the new job will be $\displaystyle\frac{{{1},{500}}}{{t}}\text{}\usepackage{cmbright}\Huge\$ square feet per hour. These two rates are equal.