[tex]1 \frac{7}{15} \times \frac{10}{11} \div 1 \frac{7}{9} \div 2 \frac{11}{12} \times \frac{9}{5} \div 7 \frac{7}{8} [/tex]
[tex] = \frac{1 \times 15 + 7}{15} \times \frac{10}{11} \div \frac{1 \times 9 + 7}{9} \div \frac{2 \times 12 + 11}{12} \times \frac{9}{5} \div \frac{7 \times 8 + 7}{8} [/tex]
[tex] = \frac{22}{15} \times \frac{10}{11} \div \frac{16}{9} \div \frac{35}{12} \times \frac{9}{5} \div \frac{63}{8} [/tex]
[tex] = \frac{22}{15} \times \frac{10}{11} \times \frac{9}{16} \times \frac{12}{35} \times \frac{9}{5} \times \frac{8}{63} [/tex]
[tex] = \frac{2}{3} \times 2 \times \frac{9}{4} \times \frac{3}{35} \times \frac{1}{5} \times \frac{8}{7} [/tex]
[tex] = 2 \times \frac{3}{2} \times \frac{3}{35} \times \frac{1}{5} \times \frac{8}{7} [/tex]
[tex] = 3 \times \frac{3}{35} \times \frac{1}{5} \times \frac{8}{7} [/tex]
[tex] = \frac{3 \times 3 \times 1 \times 8}{35 \times 5 \times 7} [/tex]
[tex] = \frac{72}{1225} [/tex]
