7. \(\frac{4}{5}-\frac{1}{3}\)

Общий знаменатель — 15: \(\frac{4}{5}=\frac{12}{15}\), \(\frac{1}{3}=\frac{5}{15}\).

\(\frac{12}{15}-\frac{5}{15}=\frac{7}{15}\).

Ответ: \(\frac{7}{15}\)