\(\begin{aligned} &\left(\frac{3}{7}+\frac{5}{3}\right)\left(1+\frac{5}{11}\right)\\ =\,&\left(\frac{9}{21}+\frac{35}{21}\right)\left(\frac{11}{11}+\frac{5}{11}\right)\\ =\,&\frac{9+35}{21}\cdot\frac{11+5}{11}\\ =\,&\frac{44}{21}\cdot\frac{16}{11}\\ =\,&\frac{4}{21}\cdot\frac{16}{1}\\ =\,&\frac{4\cdot 16}{21\cdot 1}\\ =\,&\frac{64}{21}\\=\,&\frac{3\cdot 21 + 1}{21}\\=\,&3\frac{1}{21}\\\end{aligned}\)