Страница 31, ГДЗ за 5 класс к математическому тренажеру Жохова

Д \[\begin{array}{ll} \hspace{0.8em}\begin{array}{l} \mathllap{1)\ }v = 25\text{ км/ч} \\ \underline{\mathrlap{t = 4\text{ м}}\hphantom{v = 25\text{ км/ч}}} \\ s = 25 \cdot 4 = \textcolor{#e03131}{\mathbf{100}}\text{ (км)} \\ \rule{0pt}{1.1em}\textcolor{#808080}{\text{Здесь }t = 4\text{ ч.}} \end{array} & \quad \hspace{0.8em}\begin{array}{l} \mathllap{3)\ }s = 60\text{ м} \\ \underline{t = 12\text{ мин}} \\ v = 60 : 12 = \textcolor{#e03131}{\mathbf{5}}\text{ (м/мин)} \\[1.46em] \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{2)\ }s = 51\text{ м} \\ \underline{t = 17\text{ мин}} \\ v = 51 : 17 = \textcolor{#e03131}{\mathbf{3}}\text{ (м/мин)} \end{array} & \quad \hspace{0.8em}\begin{array}{l} \mathllap{4)\ }v = 2\text{ км/ч} \\ \underline{\mathrlap{t = 6\text{ ч}}\hphantom{v = 2\text{ км/ч}}} \\ s = 2 \cdot 6 = \textcolor{#e03131}{\mathbf{12}}\text{ (км)} \end{array} \end{array}\]

Е \[\begin{array}{ll} \hspace{0.8em}\begin{array}{l} \mathllap{1)\ }s = 84\text{ км} \\ \underline{v = 12\text{ км/ч}} \\ t = 84 : 12 = \textcolor{#e03131}{\mathbf{7}}\text{ (ч)} \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{3)\ }v = 75\text{ км/ч} \\ \underline{\mathrlap{t = 4\text{ ч}}\hphantom{v = 75\text{ км/ч}}} \\ s = 75 \cdot 4 = \textcolor{#e03131}{\mathbf{300}}\text{ (км)} \\[0.09em] \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{2)\ }v = 5\text{ м/мин} \\ \underline{\mathrlap{t = 16\text{ мин}}\hphantom{v = 5\text{ м/мин}}} \\ s = 5 \cdot 16 = \textcolor{#e03131}{\mathbf{80}}\text{ (м)} \end{array} & \qquad \hspace{0.8em}\begin{array}{l} \mathllap{4)\ }v = 250\text{ м/ч} \\ \underline{\mathrlap{t = 8\text{ ч}}\hphantom{v = 250\text{ м/ч}}} \\ s = 250 \cdot 8 = \textcolor{#e03131}{\mathbf{2\,000}}\text{ (м)} \end{array} \end{array}\]

Ж \[\begin{array}{l} \hspace{0.8em}\begin{array}{l} \mathllap{1)\ }v = 2\text{ м/мин} \\ \underline{\mathrlap{t = 2\text{ ч}}\hphantom{v = 2\text{ м/мин}}} \\ s = 2 \cdot 120 = \textcolor{#e03131}{\mathbf{240}}\text{ (м)} \\ \rule{0pt}{1.1em}\textcolor{#808080}{2\text{ ч}= 120\text{ мин.}} \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{2)\ }s = 20\text{ км} \\ \underline{v = 10\text{ м/мин}} \\ t = 20\,000 : 10 = \textcolor{#e03131}{\mathbf{2\,000}}\text{ (мин)} \\ \rule{0pt}{1.1em}\textcolor{#808080}{20\text{ км}= 20\,000\text{ м.}} \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{3)\ }v = 5\text{ м/с} \\ \underline{\mathrlap{t = 1\text{ мин}}\hphantom{v = 5\text{ м/с}}} \\ s = 5 \cdot 60 = \textcolor{#e03131}{\mathbf{300}}\text{ (м)} \\ \rule{0pt}{1.1em}\textcolor{#808080}{1\text{ мин}= 60\text{ с.}} \end{array} \\ \\ \hspace{0.8em}\begin{array}{l} \mathllap{4)\ }s = 3\text{ км} \\ \underline{t = 5\text{ мин}} \\ v = 3\,000 : 5 = \textcolor{#e03131}{\mathbf{600}}\text{ (м/мин)} \\ \rule{0pt}{1.1em}\textcolor{#808080}{3\text{ км}= 3\,000\text{ м.}} \end{array} \end{array}\]