a) $\frac{-1}{8}$ + $\frac{-5}{3}$
= $\frac{-3}{24}$ + $\frac{-40}{24}$
= -$\frac{3 + 40}{24}$
= $\frac{-43}{24}$
b) $\frac{-6}{35}$ . $\frac{-49}{54}$
= $\frac{-6 }{7 . 5 }$ . $\frac{-7 . 7}{6 . 9}$
= $\frac{-6 . (-7) . 7}{7 . 5 . 6 . 9}$
= $\frac{7}{5 . 9}$
= $\frac{7}{45}$
c) $\frac{-4}{5}$ ÷ $\frac{3}{4}$
= $\frac{-4}{5}$ . $\frac{4}{3}$
= $\frac{-16}{15}$
