Ответ:

\(0,75=\frac{3}{4}\).

\[\frac{1}{5}:\frac{3}{4}=\frac{1}{5}\cdot\frac{4}{3}=\frac{4}{15}.\]

\[\frac{4}{15}+3=\frac{4}{15}+\frac{45}{15}=\frac{49}{15}=3\frac{4}{15}.\]

Ответ: \(\frac{49}{15}\).