\[Страница\ 30.\]
\[\boxed{\mathbf{1}.}\]
\[\textbf{б)}\ 58 + 94 =\]
\[= (50 + 8) + (90 + 4) =\]
\[= (50 + 90) + (8 + 4) =\]
\[= 140 + 12 = 152\]
\[\textbf{в)}\ 138 + 87 =\]
\[= (100 + 30 + 8) + (80 + 7) =\]
\[= 100 + (30 + 80) + (8 + 7) =\]
\[= 100 + 110 + 15 = 210 + 15 =\]
\[= 225\]
\[\textbf{г)}\ 830 + 291 =\]
\[= (800 + 30) + (200 + 90 + 1) =\]
\[= (800 + 200) + (30 + 90) + 1 =\]
\[= 1000 + 120 + 1 = 1121\]
\[\textbf{д)}\ 60 + 119 + 422 =\]
\[= 500 + 90 + 11 =\]
\[= 500 + 101 = 601\]
\[\boxed{\mathbf{2}.}\]
\[Таблицу\ выучить\ наизусть\ \]
\[самостоятельно.\]
\[\boxed{\mathbf{3}.}\]
\[\textbf{а)}\]
\[\textbf{б)}\]
\[\textbf{в)}\ \]