\(\left(3\frac{3}{10}+5\frac{19}{20}\right)\cdot\left(\frac{3}{4}+\frac{7}{20}\right)\)

\(3\frac{3}{10}+5\frac{19}{20}=\frac{37}{4}\), а \(\frac{3}{4}+\frac{7}{20}=\frac{11}{10}\).

\(\frac{37}{4}\cdot\frac{11}{10}=\frac{407}{40}=10\frac{7}{40}\).

Ответ: \(10\frac{7}{40}\).