\[Стр.\ 47.\]
\[\boxed{\mathbf{4.}}\]
\[\textbf{а)}\ 14 - 17 = - 3\]
\[- 3 + 17 = 14\]
\[\textbf{б)} - 8 - ( - 3) = - 5\]
\[- 5 + ( - 3) = - 8\]
\[\textbf{в)} - 3 - ( - 8) = 5\]
\[5 + ( - 8) = - 3\]
\[\textbf{г)}\ 10 - ( - 2) = 12\]
\[12 + ( - 2) = 10\]
\[\textbf{д)}\ 0 - 5 = - 5\]
\[- 5 + 5 = 0\]
\[\textbf{е)}\ 0 - ( - 7) = 7\]
\[7 + ( - 7) = 0\]
\[\textbf{ж)} - 17 - ( - 0,92) = - 16,08\]
\[- 16,08 + ( - 0,92) = - 17\]
\[\textbf{з)}\ 3\frac{2}{7} - \left( - 5\frac{1}{7} \right) = 8\frac{3}{7}\]
\[8\frac{3}{7} + \left( - 5\frac{1}{7} \right) = 3\frac{2}{7}\]
\[\textbf{и)} - 2,57 - 3 = - 5,57\]
\[- 5,57 + 3 = - 2,57\]
\[к) - 9,81 - ( - 7,99) = - 1,82\]
\[- 1,82 + ( - 7,99) = - 9,81\]
\[\boxed{\mathbf{5.}}\]
\[\textbf{а)}\ 12 - ( - 4) = 16\]
\[14 - ( - 18) = 32\]
\[- 32 - ( - 18) = - 14\]
\[\textbf{б)}\ 7,5 - 10,5 = - 3\]
\[0 - ( - 80,2) = 80,2\]
\[0 - 15,7 = - 15,7\]
\[\textbf{в)}\ 8 - ( - 8) = 16\]
\[- 2,7 - 2,7 = - 5,4\]
\[- 4,8 - ( - 3,2) = - 1,6\]
\[\textbf{г)} - 5,23 - ( - 5,23) = 0\]
\[0,71 - 0 = - 0,71\]
\[- 3\frac{1}{8} - 0,125 = - 3\frac{1}{4}\]
\[\textbf{д)}\frac{7}{12} - \left( - \frac{1}{12} \right) = \frac{2}{3}\]
\[- \frac{4}{15} - \left( - \frac{1}{15} \right) = - \frac{1}{5}\]
\[- 2\frac{2}{7} - \frac{1}{7} = - 2\frac{3}{7}\]
\[\textbf{е)} - \frac{3}{5} - \frac{1}{10} = - \frac{7}{10}\]
\[- \frac{3}{8} - \left( - \frac{7}{8} \right) = \frac{1}{2}\]
\[1\frac{3}{11} - 2\frac{5}{22} = - \frac{21}{22}\]