Страница 37, ГДЗ по математике за 2 класс к проверочным работам Волковой. Серия "Школа России" к УМК Моро

\[\begin{aligned} 7 + 8 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{1}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{5}}\kern0.035em} & \qquad 40 + 50 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{9}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{0}}\kern0.035em} & \qquad 80 + 9 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{8}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{9}}\kern0.035em} \end{aligned}\] Проверка: \[\begin{aligned} 15 - 8 &= \textcolor{#e03131}{\mathbf{7}} & \qquad 90 - 50 &= \textcolor{#e03131}{\mathbf{40}} & \qquad 89 - 9 &= \textcolor{#e03131}{\mathbf{80}} \end{aligned}\]

\[\begin{aligned} 38 - 8 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{3}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{0}}\kern0.035em} & \qquad 90 - 60 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{3}}\kern0.035em}\hspace{-0.04em}\boxed{\kern0.035em\textcolor{#e03131}{\mathbf{0}}\kern0.035em} & \qquad 13 - 4 &= \boxed{\kern0.035em\textcolor{#e03131}{\mathbf{9}}\kern0.035em} \end{aligned}\] Проверка: \[\begin{aligned} 30 + 8 &= \textcolor{#e03131}{\mathbf{38}} & \qquad 30 + 60 &= \textcolor{#e03131}{\mathbf{90}} & \qquad 9 + 4 &= \textcolor{#e03131}{\mathbf{13}} \end{aligned}\]

\(1)\ 37 - 6 = \textcolor{#e03131}{\mathbf{31}}\text{ (к.)}\)
\(2)\ 31 - 4 = \textcolor{#e03131}{\mathbf{27}}\text{ (к.)}\)
Ответ: \(\textcolor{#e03131}{\mathbf{27}}\) книг.

\[\underset{\textstyle\rule[-0.4em]{0pt}{1.4em}\textcolor{#808080}{\text{правильная запись}}}{\fcolorbox{#e03131}{#ffe3e3}{$5 + 5 - 3 = 7\text{ (к.)}$}} \qquad \boxed{5 + 5 + 3 = 13\text{ (к.)}}\]