Страница 51, ГДЗ по математике за 4 класс к самостоятельным и контрольным работам Лопатковой
Умножение и деление на числа, оканчивающиеся нулями. Самостоятельная работа № 18. Вариант 2
\[\begin{aligned} 643 \cdot 5\,000 &= \boxed{\smash[b]{\underset{\hspace{6em}}{\textcolor{#e03131}{\mathbf{3\,215\,000}}}}} \\ 34\,520 \cdot 300 &= \boxed{\smash[b]{\underset{\hspace{6em}}{\textcolor{#e03131}{\mathbf{10\,356\,000}}}}} \end{aligned}\] \[\begin{array}{cr} & \vphantom{\overset{\bullet}{0}}643\phantom{000} \\ \smash{\raisebox{0.62em}{$\times$}} & 5000 \\ \hline & \textcolor{#e03131}{\mathbf{3}\kern-0.075em\mathbf{2}\kern-0.075em\mathbf{1}\kern-0.075em\mathbf{5}\kern-0.075em\mathbf{0}\kern-0.075em\mathbf{0}\kern-0.075em\mathbf{0}\kern-0.075em} \end{array} \qquad \begin{array}{cr} & \vphantom{\overset{\bullet}{0}}34520\phantom{00} \\ \smash{\raisebox{0.62em}{$\times$}} & 300\phantom{0} \\ \hline & \textcolor{#e03131}{\mathbf{1}\kern-0.075em\mathbf{0}\kern-0.075em\mathbf{3}\kern-0.075em\mathbf{5}\kern-0.075em\mathbf{6}\kern-0.075em\mathbf{0}\kern-0.075em\mathbf{0}\kern-0.075em\mathbf{0}\kern-0.075em} \end{array}\]
\(1)\ 560 - 160 = \textcolor{#e03131}{\mathbf{400}}\text{ (км)}\)
\(2)\ 400 : 10 = \textcolor{#e03131}{\mathbf{40}}\text{ (км/ч)}\)
\(3)\ 160 : 40 = \textcolor{#e03131}{\mathbf{4}}\text{ (ч)}\)
Ответ: за \(\textcolor{#e03131}{\mathbf{4}}\) ч.

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