Страница 31, ГДЗ по математике за 3 класс к проверочным работам Волковой. Серия "Школа России" к УМК Моро
Умножение и деление (продолжение). Площадь прямоугольника (квадрата). Проверочная работа 1. Вариант 2
2) Найди периметр прямоугольника \(ABCD\).
\(P = (2 + 4) \cdot 2 = \textcolor{#e03131}{\mathbf{12}}\text{ (см)}\)
3) Найди площадь прямоугольника \(ABCD\).
\(S = 2 \cdot 4 = \textcolor{#e03131}{\mathbf{8}}\text{ (см}^2\text{)}\)
Ответ: 2) \(\textcolor{#e03131}{\mathbf{12}}\) см; 3) \(\textcolor{#e03131}{\mathbf{8}}\) см².
\[\begin{array}{|c|c|c|c|c|} \hline 7 & 5 & 8 & 6 & 9 \\ \hline \rule[-0.52em]{0pt}{1.66em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{4}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{9}}\kern0.035em} & \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{3}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{5}}\kern0.035em} & \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{5}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{6}}\kern0.035em} & \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{4}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{2}}\kern0.035em} & \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{6}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{3}}\kern0.035em} \\ \hline \end{array}\] Уменьши в 5 раз \[\begin{array}{|c|c|c|c|c|} \hline 40 & 25 & 15 & 30 & 45 \\ \hline \rule[-0.52em]{0pt}{1.66em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{8}}\kern0.035em} & \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{5}}\kern0.035em} & \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{3}}\kern0.035em} & \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{6}}\kern0.035em} & \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{9}}\kern0.035em} \\ \hline \end{array}\]
\[\begin{aligned} 45 \mathrel{\overset{\textcolor{#1a7f37}{1}}{\vphantom{+}{:}}} 5 \mathbin{\overset{\textcolor{#1a7f37}{2}}{\vphantom{+}\cdot}} 6 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{5}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{4}}\kern0.035em} & \qquad 56 \mathrel{\overset{\textcolor{#1a7f37}{1}}{\vphantom{+}{:}}} 7 \mathbin{\overset{\textcolor{#1a7f37}{2}}{\vphantom{+}\cdot}} 3 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{2}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{4}}\kern0.035em} \\ (40 \overset{\textcolor{#1a7f37}{1}}{-} 4) \mathrel{\overset{\textcolor{#1a7f37}{2}}{\vphantom{+}{:}}} 9 \mathbin{\overset{\textcolor{#1a7f37}{3}}{\vphantom{+}\cdot}} 7 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{2}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{8}}\kern0.035em} \end{aligned}\]
\[\textcolor{#e03131}{\mathbf{13}}\textcolor{#e03131}{\mathbf{,}}\ \textcolor{#e03131}{\mathbf{26}}\textcolor{#e03131}{\mathbf{,}}\ \textcolor{#e03131}{\mathbf{39}}\] \(\textcolor{#808080}{{3 = 1 \cdot 3}\text{, }{6 = 2 \cdot 3}\text{, }{9 = 3 \cdot 3}}\)
