Ответ:

а) \(\frac{7}{8}-\left(x+\frac{5}{12}\right)=\frac{5}{24}\)

Перенесём скобки в правую часть:

\(x+\frac{5}{12}=\frac{7}{8}-\frac{5}{24}=\frac{21}{24}-\frac{5}{24}=\frac{16}{24}=\frac{2}{3}\).

\(x=\frac{2}{3}-\frac{5}{12}=\frac{8}{12}-\frac{5}{12}=\frac{1}{4}\).

б) \(\left(\frac{2}{15}+y\right)-\frac{7}{30}=\frac{1}{10}\)

\(\frac{2}{15}+y=\frac{1}{10}+\frac{7}{30}=\frac{3}{30}+\frac{7}{30}=\frac{1}{3}\).

\(y=\frac{1}{3}-\frac{2}{15}=\frac{5}{15}-\frac{2}{15}=\frac{1}{5}\).

Ответ: а) \(x=\frac{1}{4}\); б) \(y=\frac{1}{5}\).