Страница 48, ГДЗ по математике за 3 класс к тренажёру Погореловой
Сложение и вычитание. Приёмы устных вычислений
\[\begin{aligned} 329 + 1 &= \textcolor{#e03131}{\mathbf{330}} & \qquad 699 + 1 &= \textcolor{#e03131}{\mathbf{700}} \\ 900 - 1 &= \textcolor{#e03131}{\mathbf{899}} & \qquad 840 - 1 &= \textcolor{#e03131}{\mathbf{839}} \\ 509 + 1 &= \textcolor{#e03131}{\mathbf{510}} & \qquad 349 + 1 &= \textcolor{#e03131}{\mathbf{350}} \\ 410 - 1 &= \textcolor{#e03131}{\mathbf{409}} & \qquad 700 - 1 &= \textcolor{#e03131}{\mathbf{699}} \end{aligned}\]
\[\begin{aligned} 4\text{ сот.} + 3\text{ сот.} &= \textcolor{#e03131}{\mathbf{7}}\text{ сот.} & \quad 700 - 500 &= \textcolor{#e03131}{\mathbf{200}} \\ 8\text{ сот.} - 2\text{ сот.} &= \textcolor{#e03131}{\mathbf{6}}\text{ сот.} & \quad 200 + 400 &= \textcolor{#e03131}{\mathbf{600}} \\ 5\text{ сот.} - 4\text{ сот.} &= \textcolor{#e03131}{\mathbf{1}}\text{ сот.} & \quad 900 - 300 &= \textcolor{#e03131}{\mathbf{600}} \\ 3\text{ сот.} + 6\text{ сот.} &= \textcolor{#e03131}{\mathbf{9}}\text{ сот.} & \quad 600 + 100 &= \textcolor{#e03131}{\mathbf{700}} \\ 8\text{ сот. }3\text{ дес.} + 9\text{ дес.} &= \textcolor{#e03131}{\mathbf{9}}\text{ сот. }\textcolor{#e03131}{\mathbf{2}}\text{ дес.} & \quad 480 + 70 &= \textcolor{#e03131}{\mathbf{550}} \\ 6\text{ сот. }1\text{ дес.} - 5\text{ дес.} &= \textcolor{#e03131}{\mathbf{5}}\text{ сот. }\textcolor{#e03131}{\mathbf{6}}\text{ дес.} & \quad 920 - 40 &= \textcolor{#e03131}{\mathbf{880}} \\ 3\text{ сот. }6\text{ дес.} + 7\text{ дес.} &= \textcolor{#e03131}{\mathbf{4}}\text{ сот. }\textcolor{#e03131}{\mathbf{3}}\text{ дес.} & \quad 250 + 90 &= \textcolor{#e03131}{\mathbf{340}} \\ 7\text{ сот. }4\text{ дес.} - 6\text{ дес.} &= \textcolor{#e03131}{\mathbf{6}}\text{ сот. }\textcolor{#e03131}{\mathbf{8}}\text{ дес.} & \quad 530 - 60 &= \textcolor{#e03131}{\mathbf{470}} \\ 4\text{ сот. }7\text{ дес.} + 2\text{ сот. }5\text{ дес.} &= \textcolor{#e03131}{\mathbf{7}}\text{ сот. }\textcolor{#e03131}{\mathbf{2}}\text{ дес.} \\ 8\text{ сот. }5\text{ дес.} - 3\text{ сот. }8\text{ дес.} &= \textcolor{#e03131}{\mathbf{4}}\text{ сот. }\textcolor{#e03131}{\mathbf{7}}\text{ дес.} \\ 6\text{ сот. }4\text{ дес.} - 4\text{ сот. }6\text{ дес.} &= \textcolor{#e03131}{\mathbf{1}}\text{ сот. }\textcolor{#e03131}{\mathbf{8}}\text{ дес.} \\ 3\text{ сот. }8\text{ дес.} + 5\text{ сот. }4\text{ дес.} &= \textcolor{#e03131}{\mathbf{9}}\text{ сот. }\textcolor{#e03131}{\mathbf{2}}\text{ дес.} \end{aligned}\]
