\[\boxed{\mathbf{2.}\mathbf{387}}\]
Пояснение.
Решение.
\[\textbf{а)}\ \frac{3^{\backslash 3}}{5}x + \frac{2}{15}x - \frac{4}{15}x =\]
\[= \frac{9}{15}x + \frac{2}{15}x - \frac{4}{15}x =\]
\[= \left( \frac{9}{15} + \frac{2}{15} - \frac{4}{15} \right)x = \frac{7}{15}x\]
\[\textbf{б)}\ \frac{3^{\backslash 2}}{4}a - \frac{5}{8}a + \frac{7}{8}a =\]
\[= \frac{6}{8}a - \frac{5}{8}a + \frac{7}{8}a =\]
\[= \left( \frac{6}{8} - \frac{5}{8} + \frac{7}{8} \right)a = \frac{8}{8}a = a\]
\[\textbf{в)}\ \frac{7}{24}z + \left( \frac{11^{\backslash 2}}{12}z - \frac{2^{\backslash 8}}{3}z \right) =\]
\[= \frac{7}{24}z + \frac{22}{24}z - \frac{16}{24}z =\]
\[= \left( \frac{7}{24} + \frac{22}{24} - \frac{16}{24} \right)z = \frac{13}{24}z\]
\[\textbf{г)}\ \frac{9}{14}c - \left( \frac{3}{14}c + \frac{2^{\backslash 2}}{7}c \right) =\]
\[= \frac{9}{14}c - \frac{3}{14}c - \frac{4}{14}c =\]
\[= \left( \frac{9}{14} - \frac{3}{14} - \frac{4}{14} \right)c =\]
\[= \frac{2}{14}c = \frac{1}{7}c\]