You may rewrite $\displaystyle{6.82}={6.820}\usepackage{cmbright}\Huge\$ . Now compare the digits of 6.820 and 6.823. The digits in the ones, tenths, and hundredths place are the same. Comparing the digits in the thousandths place, $\displaystyle{3}>{0}\usepackage{cmbright}\Huge\$ . Therefore, $\displaystyle{6.823}>{6.82}\usepackage{cmbright}\Huge\$ . Remember that > means "greater than."