Решебник по математике 6 класс Ерина Никольский рабочая тетрадь Часть 1, 2 Часть 1 | Страница 12

\[\mathbf{Страница\ 12.}\]

\[\boxed{\mathbf{1.}}\]

\[\textbf{а)}\ отношений.\]

\[\textbf{б)}\ крайних;средних.\]

\[\boxed{\mathbf{2.}}\]

\[1)\ 5\ :2 = 10\ :4\]

\[Крайние\ члены:\ \ \ 5\ и\ 4.\]

\[Средние\ члены:\ \ \ 2\ и\ 10.\]

\[2)\ Пропорция:\ \ \ \ \ \]

\[12\ :18 = 24\ :36\]

\[3)\ \frac{8}{9} = \frac{24}{27}\]

\[Крайние\ члены:\ \ 8\ и\ 27.\]

\[Средние\ члены:\ 9\ и\ 24.\ \]

\[4)\ a\ :b = c\ :d\]

\[Крайние\ члены:a\ и\ \text{d.}\]

\[Средние\ члены:\ b\ и\ \text{c.}\]

\[\boxed{\mathbf{3.}}\]

\[\textbf{а)}\ \frac{90}{6} = \frac{45}{3}\]

\[90\ :6 = 45\ :3\]

\[90 \cdot 3 = 45 \cdot 6\]

\[\textbf{б)}\ \frac{16}{48} = \frac{17}{51}\]

\[16\ :48 = 17\ :51\]

\[16 \cdot 51 = 48 \cdot 17\]

\[\boxed{\mathbf{4.}}\]

\[\textbf{а)}\ 2\frac{2}{5}\ :\frac{4}{5} = \frac{12}{5}\ :\frac{4}{5} = \frac{12}{4} = \frac{3}{1}\]

\[\textbf{б)}\ 6\frac{2}{5}\ :1\frac{3}{5} = \frac{32}{5}\ :\frac{8}{5} = \frac{32}{8} = \frac{4}{1}\]

\[\textbf{в)}\ 2\frac{3}{13}\ :\frac{29}{39} = \frac{29}{13}\ :\frac{29}{39} = \frac{39}{13} = \frac{3}{1}\]

\[Верная\ пропорция:\]

\[2\frac{2}{5}\ :\frac{4}{5} = 2\frac{3}{13}\ :\frac{29}{39}.\]

\[\boxed{\mathbf{5.}}\]

\[4\frac{2}{7}\ :53\frac{1}{3} = \frac{30}{7}\ :\frac{160}{3} = \frac{9}{112}\]

\[22\frac{1}{2}\ :280 = \frac{45}{2}\ :\frac{280}{1} = \frac{9}{112}\]

\[Пропорция:\ \]

\[4\frac{2}{7}\ :53\frac{1}{3} = 22\frac{1}{2}\ :280.\]