1. $$\left(\frac{6}{5} - \frac{3}{4}\right) \cdot \frac{2}{3} = \left(\frac{24}{20} - \frac{15}{20}\right) \cdot \frac{2}{3} = \frac{9}{20} \cdot \frac{2}{3} = \frac{3}{10}$$
2. $$\left(\frac{6}{5} - \frac{2}{3}\right) \cdot \frac{1}{2} = \left(\frac{18}{15} - \frac{10}{15}\right) \cdot \frac{1}{2} = \frac{8}{15} \cdot \frac{1}{2} = \frac{4}{15}$$
3. $$\frac{18}{29} \cdot \frac{9}{5} \cdot \frac{16}{6} = \frac{18 \cdot 9 \cdot 16}{29 \cdot 5 \cdot 6} = \frac{2592}{870} = \frac{432}{145}$$
4. $$\frac{30}{18} \div \frac{18}{25} = \frac{30}{18} \cdot \frac{25}{18} = \frac{30 \cdot 25}{18 \cdot 18} = \frac{750}{324} = \frac{125}{54}$$
5. $$\frac{8}{5} \cdot \left(\frac{3}{4} + \frac{11}{8}\right) = \frac{8}{5} \cdot \left(\frac{6}{8} + \frac{11}{8}\right) = \frac{8}{5} \cdot \frac{17}{8} = \frac{17}{5}$$
6. $$\frac{18}{7} \cdot \left(\frac{4}{9} + \frac{15}{18}\right) = \frac{18}{7} \cdot \left(\frac{8}{18} + \frac{15}{18}\right) = \frac{18}{7} \cdot \frac{23}{18} = \frac{23}{7}$$
7. $$\frac{8}{5} \div \frac{3}{4} + \frac{11}{8} = \frac{8}{5} \cdot \frac{4}{3} + \frac{11}{8} = \frac{32}{15} + \frac{11}{8} = \frac{256}{120} + \frac{165}{120} = \frac{421}{120}$$
8. $$\frac{18}{7} \div \frac{4}{9} + \frac{15}{14} = \frac{18}{7} \cdot \frac{9}{4} + \frac{15}{14} = \frac{162}{28} + \frac{15}{14} = \frac{81}{14} + \frac{15}{14} = \frac{96}{14} = \frac{48}{7}$$
9. $$72 \cdot \left(\frac{19}{24} - \frac{7}{12} + \frac{3}{8}\right) = 72 \cdot \left(\frac{19}{24} - \frac{14}{24} + \frac{9}{24}\right) = 72 \cdot \frac{14}{24} = 72 \cdot \frac{7}{12} = 6 \cdot 7 = 42$$
10. $$\frac{72}{73} \cdot \frac{34}{65} + \frac{72}{73} \cdot \frac{39}{65} = \frac{72}{73} \cdot \left(\frac{34}{65} + \frac{39}{65}\right) = \frac{72}{73} \cdot \frac{73}{65} = \frac{72}{65}$$