Решебник по математике 6 класс Мерзляк ФГОС Задание 397

\[\boxed{\mathbf{397\ (397).}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]

Пояснение.

Решение.

\[16\% = 0,16\]

\[140 \cdot 0,16 = 22,4\ (га) -\]

\[площадь\ сада.\]

\[Ответ:22,4\ га.\]

\[\boxed{\mathbf{397}\mathbf{.}}\]

\[1)\ \left( 2\frac{7}{10} - 1\frac{8}{15} \right)^{2} \cdot \frac{9}{14} = \frac{7}{8}\]

\[2\frac{7^{\backslash 3}}{10} - 1\frac{8^{\backslash 2}}{15} = 2\frac{21}{30} - 1\frac{16}{30} =\]

\[= 1\frac{5}{30} = 1\frac{1}{6}\]

\[\left( 1\frac{1}{6} \right)^{2} = \left( \frac{7}{6} \right)^{2} = \frac{49}{36}\]

\[\frac{49}{36} \cdot \frac{9}{14} = \frac{7 \cdot 1}{4 \cdot 2} = \frac{7}{8}\]

\[2)\ 9\frac{5}{6} - \left( 4 - 6\frac{1}{8} \cdot \frac{2}{7} \right)\ :1\frac{5}{22} = 8\]

\[6\frac{1}{8} \cdot \frac{2}{7} = \frac{49}{8} \cdot \frac{2}{7} = \frac{7 \cdot 1}{4 \cdot 1} = \frac{7}{4} = 1\frac{3}{4}\]

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

\[2\frac{1}{4}\ :1\frac{5}{22} = \frac{9}{4}\ :\frac{27}{22} = \frac{9}{4} \cdot \frac{22}{27} =\]

\[= \frac{1 \cdot 11}{2 \cdot 3} = \frac{11}{6} = 1\frac{5}{6}\]

\[9\frac{5}{6} - 1\frac{5}{6} = 8\]