Correct. 7875 can be factored into $\displaystyle{25}\cdot{9}\cdot{35}\usepackage{cmbright}\Huge\$ , and 25 and 9 are square numbers. $\displaystyle\sqrt{{7875}}=\sqrt{{{{5}}^{{2}}\cdot{{3}}^{{2}}\cdot{35}}}={5}\cdot{3}\cdot\sqrt{{35}}={15}\sqrt{{35}}\usepackage{cmbright}\Huge\$ .