[tex]1 \frac{2}{3} - \frac{5}{6} + 2 \frac{1}{10} \div 1 \frac{6}{15} = \frac{5}{3} - \frac{5}{6} + \frac{21}{10} \div \frac{21}{15} = \frac{10}{6} - \frac{5}{6} + \frac{21}{10} \times \frac{15}{21} = \frac{5}{6} + \frac{3}{2} = \frac{5}{6} + \frac{9}{6}=\frac{14}{6}=\frac{7}{3}=2\frac{1}{3} [/tex]
