ГДЗ по математике 3 класс Петерсон рабочая тетрадь Часть 1, 2, 3 Часть 2 | Страница 56

\[\boxed{\mathbf{Страница\ 56.\ }\mathbf{Еуроки\ - \ ДЗ\ без\ мороки}}\]

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

\[\mathbf{1.}\]

\[\textbf{а)}\ x + 4 = a\]

\[x = a - 4\]

\[\textbf{б)}\ x\ :3 = b\]

\[x = b \cdot 3\]

\[\textbf{в)}\ c\ :x = 5\]

\[x = c\ :5\]

\[\textbf{г)}\ k - x = d\]

\[x = k - d\]

\[\textbf{д)}\ 8 \cdot x = n\]

\[x = n\ :8\]

\[\textbf{е)}\ x - p = s\]

\[x = s + p\]

\[\mathbf{2.}\]

\[15\ :(8 - x) + 9 = 12\]

\[15\ :(8 - x) = 12 - 9\]

\[15\ :(8 - x) = 3\]

\[8 - x = 15\ :3\]

\[8 - x = 5\]

\[x = 8 - 5\]

\[x = 3\]

\[Ответ:x = 3.\]

\[(8 \cdot x - 140)\ :6 = 30\]

\[8 \cdot x - 140 = 30 \cdot 6\]

\[8 \cdot x - 140 = 180\]

\[8 \cdot x = 180 + 140\]

\[8 \cdot x = 320\]

\[x = 320\ :8\]

\[x = 40\]

\[Ответ:x = 40.\]

\[\mathbf{3.}\]

\[22\ ч\ 12\ мин - 4\ ч\ 46\ мин =\]

\[= 21\ ч\ 72\ мин - 4\ ч\ 46\ мин =\]

\[= 17\ ч\ 26\ мин -\]

\[долгота\ этого\ дня.\]

\[Ответ:17\ ч\ 26\ мин.\]

\[\mathbf{4.}\]

\[\{ 420;\ \ 402;\ \ 240;\ \ 204\}.\]

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

\[\mathbf{1.}\]

\[\textbf{а)}\ x \cdot 6 = c\]

\[x = c\ :6\]

\[\textbf{б)}\ n\ :x = 9\]

\[x = n\ :9\]

\[\textbf{в)}\ 72 - x = n\]

\[x = 72 - n\]

\[\textbf{г)}\ x - b = m\]

\[x = m + b\]

\[\textbf{д)}\ x\ :7 = t\]

\[x = t \cdot 7\]

\[\textbf{е)}\ k + x = d\]

\[x = d - k\]