Страница 30, ГДЗ за 5 класс к математическому тренажеру Жохова

А \[\begin{array}{ll} \hspace{0.8em}\begin{array}{l} \mathllap{1)\ }v = 20\text{ км/ч} \\ \underline{\mathrlap{t = 4\text{ ч}}\hphantom{v = 20\text{ км/ч}}} \\ s = 20 \cdot 4 = \textcolor{#e03131}{\mathbf{80}}\text{ (км)} \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{3)\ }s = 12\text{ м} \\ \underline{\mathrlap{t = 3\text{ с}}\hphantom{s = 12\text{ м}}} \\ v = 12 : 3 = \textcolor{#e03131}{\mathbf{4}}\text{ (м/с)} \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{2)\ }s = 60\text{ см} \\ \underline{v = 15\text{ см/с}} \\ t = 60 : 15 = \textcolor{#e03131}{\mathbf{4}}\text{ (с)} \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{4)\ }v = 6\text{ км/ч} \\ \underline{\mathrlap{t = 3\text{ ч}}\hphantom{v = 6\text{ км/ч}}} \\ s = 6 \cdot 3 = \textcolor{#e03131}{\mathbf{18}}\text{ (км)} \\[0.09em] \end{array} \end{array}\]

Б \[\begin{array}{ll} \hspace{0.8em}\begin{array}{l} \mathllap{1)\ }v = 10\text{ км/ч} \\ \underline{\mathrlap{t = 8\text{ ч}}\hphantom{v = 10\text{ км/ч}}} \\ s = 10 \cdot 8 = \textcolor{#e03131}{\mathbf{80}}\text{ (км)} \\[0.09em] \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{3)\ }s = 12\text{ км} \\ \underline{v = 3\text{ км/ч}} \\ t = 12 : 3 = \textcolor{#e03131}{\mathbf{4}}\text{ (ч)} \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{2)\ }s = 90\text{ км} \\ \underline{\mathrlap{t = 6\text{ ч}}\hphantom{s = 90\text{ км}}} \\ v = 90 : 6 = \textcolor{#e03131}{\mathbf{15}}\text{ (км/ч)} \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{4)\ }s = 10\text{ м} \\ \underline{t = 2\text{ мин}} \\ v = 10 : 2 = \textcolor{#e03131}{\mathbf{5}}\text{ (м/мин)} \end{array} \end{array}\]

В \[\begin{array}{ll} \hspace{0.8em}\begin{array}{l} \mathllap{1)\ }v = 6\text{ м/мин} \\ \underline{\mathrlap{t = 15\text{ мин}}\hphantom{v = 6\text{ м/мин}}} \\ s = 6 \cdot 15 = \textcolor{#e03131}{\mathbf{90}}\text{ (м)} \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{3)\ }s = 8\text{ км} \\ \underline{\mathrlap{t = 2\text{ ч}}\hphantom{s = 8\text{ км}}} \\ v = 8 : 2 = \textcolor{#e03131}{\mathbf{4}}\text{ (км/ч)} \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{2)\ }t = 8\text{ ч} \\ \underline{v = 125\text{ км/ч}} \\ s = 125 \cdot 8 = \textcolor{#e03131}{\mathbf{1\,000}}\text{ (км)} \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{4)\ }s = 68\text{ м} \\ \underline{v = 17\text{ м/с}} \\ t = 68 : 17 = \textcolor{#e03131}{\mathbf{4}}\text{ (с)} \end{array} \end{array}\]

Г \[\begin{array}{ll} \hspace{0.8em}\begin{array}{l} \mathllap{1)\ }v = 12\text{ км/ч} \\ \underline{\mathrlap{t = 5\text{ ч}}\hphantom{v = 12\text{ км/ч}}} \\ s = 12 \cdot 5 = \textcolor{#e03131}{\mathbf{60}}\text{ (км)} \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{3)\ }s = 57\text{ км} \\ \underline{t = 19\text{ мин}} \\ v = 57 : 19 = \textcolor{#e03131}{\mathbf{3}}\text{ (км/мин)} \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{2)\ }v = 150\text{ м/с} \\ \underline{\mathrlap{t = 4\text{ с}}\hphantom{v = 150\text{ м/с}}} \\ s = 150 \cdot 4 = \textcolor{#e03131}{\mathbf{600}}\text{ (м)} \\[0.09em] \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{4)\ }s = 70\text{ км} \\ \underline{v = 14\text{ км/ч}} \\ t = 70 : 14 = \textcolor{#e03131}{\mathbf{5}}\text{ (ч)} \end{array} \end{array}\]