[tex]a) \\\\\frac{5}{6}+\frac{7}{8} =\frac{40}{48} +\frac{42}{48}=\frac{88}{48} = \frac{22}{12} = \frac{11}{6}=1\frac{5}{6} \\\\b)\\\\5\frac{2}{9} - 1\frac{5}{6}= \frac{49}{9} - \frac{11}{6} = \frac{98}{18} - \frac{33}{18} = \frac{65}{18} = 3 \frac{11}{18} \\\\c) \\\\\frac{4}{7} * 2\frac{5}{8} = \frac{4}{7} * \frac{21}{8} = \frac{1}{1} * \frac{3}{2} = \frac{3}{2}\\\\[/tex]
[tex]d) \\\\2\frac{4}{9} : 3\frac{2}{3} = \frac{22}{9} : \frac{11}{3} = \frac{22}{9} * \frac{3}{11} = \frac{2}{3} * \frac{1}{1} = \frac{2}{3}[/tex]
