\[Стр.\ 64.\]
\[\boxed{\mathbf{5.}}\]
\[\boxed{\mathbf{6.}}\]
\[\textbf{б)} - \frac{1}{3} + \frac{2}{27} + \frac{1}{3} + \frac{25}{27} =\]
\[= \left( - \frac{1}{3} + \frac{1}{3} \right) + \left( \frac{2}{27} + \frac{25}{27} \right) =\]
\[= 0 + 1 = 1\]
\[\textbf{в)} - 7,56 + 9,2 + 7,56 - 4,6 =\]
\[= 0 + 4,6 = 4,6\]
\[\textbf{г)}\frac{4}{21} + \left( \frac{5}{11} - \frac{4}{21} \right) =\]
\[= \left( \frac{4}{21} - \frac{4}{21} \right) + \frac{5}{11} = 0 + \frac{5}{11} =\]
\[= \frac{5}{11}\]
\[\textbf{д)} - \frac{16}{71} + \left( \frac{16}{71} + \frac{1}{3} \right) =\]
\[= \left( - \frac{16}{71} + \frac{16}{71} \right) + \frac{1}{3} = 0 + \frac{1}{3} = \frac{1}{3}\]
\[\textbf{е)}\ \left( \frac{2}{59} + \frac{25}{71} \right) + \left( - \frac{25}{71} \right) =\]
\[= \frac{2}{59} + \left( \frac{25}{71} - \frac{25}{71} \right) = \frac{2}{59} + 0 =\]
\[= \frac{2}{59}\]