Ответ:

[tex] - 1.8 \times ( - 4.5) = 8.1[/tex]

[tex] - 4 \frac{2}{5} \times \frac{10}{11} = - \frac{22}{5} \times \frac{10}{11} = - \frac{2}{1} \times \frac{2}{1} = - 4[/tex]

[tex]6.3 \times ( - \frac{2}{3} ) = 6 \frac{3}{10} \times ( - \frac{2}{3} ) = \frac{63}{10} \times ( - \frac{2}{3} ) = \frac{21}{5} \times ( - \frac{1}{1} ) = - \frac{21}{5} = - 4 \frac{1}{5} = - 4.2[/tex]