\[\boxed{\mathbf{Страница\ 57.\ }\mathbf{Еуроки\ - \ ДЗ\ без\ мороки}}\]
\[\mathbf{2.}\]
\[(x\ :8 - 4) \cdot 7 = 35\]
\[x\ :8 - 4 = 35\ :7\]
\[x\ :8 - 4 = 5\]
\[x\ :8 = 5 + 4\]
\[x\ :8 = 9\]
\[x = 9 \cdot 8\]
\[x = 72\]
\[Ответ:x = 72.\]
\[380\ :(12 - x) - 15 = 23\]
\[380\ :(12 - x) = 23 + 15\]
\[380\ :(12 - x) = 38\]
\[12 - x = 380\ :38\]
\[12 - x = 10\]
\[x = 12 - 10\]
\[x = 2\]
\[Ответ:x = 2.\]
\[\mathbf{3.}\]
\[7\ ч\ 45\ мин + 3\ ч\ 39\ мин =\]
\[= 10\ ч\ 84\ мин = 11\ ч\ 24\ мин -\]
\[самолет\ приземлился.\]
\[Ответ:в\ 11\ ч\ 24\ мин.\]
\[\mathbf{4.}\]
\[\{ 805;850;508;580\}.\]
\[\boxed{\mathbf{3.\ }}\]
\[1)\ 1\ 847\ 200\ :800 =\]
\(= 18\ 472\ :8 = 2309\)
\[2)\ 6975 + 2309 = 9284\]
\[\boxed{\mathbf{4.\ }}\]
\[Числа:\ \ \ \ 25\ и\ 1.\]
\[25 \cdot 1 = 25\]
\[25\ :1 = 25\]
\[Урок\ 38.\ Формулы\]