[tex]a) \: 2 \frac{2}{3} + 1 \frac{1}{2} + \frac{5}{6} = 2 \frac{4}{6} + 1 \frac{3}{6} + \frac{5}{6} = 3 \frac{7}{6} + \frac{5}{6} = 4 \frac{1}{6} + \frac{5}{6} = 4 \frac{6}{6} = 5[/tex]
[tex]b) \: 3 - 1 \frac{4}{9} = 1 \frac{5}{9} [/tex]
[tex]c) \: 2 \frac{1}{4} \times 1 \frac{5}{6} = \frac{9}{4} \times \frac{11}{6} = \frac{3}{4} \times \frac{11}{2} = \frac{33}{8} = 4 \frac{1}{8} [/tex]
[tex]d) \: 1 \frac{3}{10} \div 1 \frac{4}{5} = \: \frac{13}{10} \div \frac{9}{5} = \frac{13}{10} \times \frac{5}{9} = \frac{13}{2} \times \frac{1}{9} = \frac{13}{18} [/tex]
