This answer gives the correct total number of items sold, but not the correct total revenue. Twenty T-shirts sell for $\displaystyle{20}\cdot{12}={240}\usepackage{cmbright}\Huge\$ dollars, while 21 pairs of shorts sell for $\displaystyle{21}\cdot{8}={168}\usepackage{cmbright}\Huge\$ dollars. This would be a total of $408, not $416. The correct equations with which to start the problem are:

(A) $\displaystyle{t}+{s}={41}\usepackage{cmbright}\Huge\$

(B) $\displaystyle{12}{t}+{8}{s}={416}\usepackage{cmbright}\Huge\$