You get $\displaystyle\frac{{2}}{{3}}\cdot{\left(\frac{{1}}{{5}}\cdot\frac{{5}}{{2}}\right)}\usepackage{cmbright}\Huge\$ by using the associative property to regroup. Then you get $\displaystyle\frac{{2}}{{3}}\cdot{\left(\frac{{5}}{{2}}\cdot\frac{{1}}{{5}}\right)}\usepackage{cmbright}\Huge\$ by applying the commutative property.