[tex]\frac{\frac{1}{6} +\big(-\frac{2}{3}\big)\cdot\big(\frac{5}{2} \big)}{1+\frac{1}{2} }=\frac{\frac{1}{6} +\big(-\frac{10}{6}\big)}{\frac{2}{2}+\frac{1}{2}}=\frac{\frac{1}{6} -\frac{10}{6}}{\frac{2+1}{2}}=\frac{\frac{1-10}{6}}{3/2}=\frac{-9/6}{3/2}=\big(-\frac{9}{6} \big)\cdot\frac{2}{3}=-\frac{18}{18} =-1[/tex]
