[tex] - \frac{5}{7} + 1 \frac{1}{6} = - \frac{30}{42} + 1 \frac{7}{42} = \\ - \frac{30}{42} + \frac{49}{42} = \frac{19}{42} [/tex]

[tex]36 \div ( - \frac{4}{9} ) = - \frac{36 \times 9}{4} = - 9 \times 9 = - 81[/tex]

[tex]4 \frac{2}{3} \times ( - 1 \frac{4}{7} ) = - \frac{14 \times 11}{3 \times 7} = - \frac{22}{3} = - 7 \frac{1}{3} [/tex]