Решебник по математике 6 класс Виленкин ФГОС Часть 1, 2 Часть 2. П. 4. Действия с рациональными числами Задание 380

\[\boxed{\text{4.\ 380}}\]

\[\textbf{а)} - \frac{2}{5} \cdot \frac{1}{2} = - \frac{1}{5}\]

\[- 2 \cdot \frac{1}{2} = - 1\]

\[\frac{8}{11} \cdot \frac{1}{2} = \frac{4}{11}\]

\[- \frac{2}{7} \cdot \frac{1}{2} = - \frac{1}{7}\]

\[- 8 \cdot \frac{1}{2} = - 4\]

\[2\frac{2}{7} \cdot \frac{1}{2} = \frac{16}{7} \cdot \frac{1}{2} = \frac{8}{7} = 1\frac{1}{7}\]

\[- 4 \cdot \frac{1}{2} = - 2\]

\[1,2 \cdot \frac{1}{2} = 0,6\]

\[\textbf{б)}\ 8\ :\frac{3}{4} = 8 \cdot \frac{4}{3} = \frac{32}{3} = 10\frac{2}{3}\]

\[- 2\frac{2}{5}\ :\frac{3}{4} = - \frac{12}{5} \cdot \frac{4}{3} = - \frac{16}{5} =\]

\[= - 3\frac{1}{5}\]

\[- 3\ :\frac{3}{4} = - 3 \cdot \frac{4}{3} = - 4\]

\[- \frac{1}{2}\ :\frac{3}{4} = - \frac{1}{2} \cdot \frac{4}{3} = - \frac{2}{3}\]

\[- 6\ :\frac{3}{4} = - 6 \cdot \frac{4}{3} = - 2 \cdot 4 = - 8\]

\[\frac{1}{4}\ :\frac{3}{4} = \frac{1}{4} \cdot \frac{4}{3} = \frac{1}{3}\]

\[- 1\frac{1}{3}\ :\frac{3}{4} = - \frac{4}{3}\ :\frac{3}{4} = - \frac{4}{3} \cdot \frac{4}{3} =\]

\[= - \frac{16}{9} = - 1\frac{7}{9}\]