You probably found the correct quotient $\displaystyle{0.65}\times{{10}}^{{13}}\usepackage{cmbright}\Huge\$ , but when converting 0.65 to scientific notation, you incorrectly wrote it as $\displaystyle{6.5}\times{{10}}^{{1}}\usepackage{cmbright}\Huge\$ , instead of $\displaystyle{6.5}\times{{10}}^{{-{{1}}}}\usepackage{cmbright}\Huge\$ .