[tex]a. \: \: \frac{5}{9} + \frac{3}{9} - \frac{4}{9} = \frac{5 + 3 - 4}{9} = \frac{4}{9} \\ \\ b. \: \: \frac{8}{8} - \frac{5}{8} + \frac{1}{8} + \frac{2}{8} = \frac{8 - 5 + 1 + 2 }{8} = \frac{6}{8} = \frac{3}{4} \\ \\ c. \: \: \frac{8}{10} - \frac{6}{10} + \frac{3}{10} = \frac{8 - 6 + 3}{10} = \frac{5}{10} = \frac{1}{2} \\ \\ d. \: \: \frac{4}{6} + \frac{2}{6} - \frac{5}{6} + \frac{1}{6} = \frac{4 + 2 - 5 + 1}{6} = \frac{2}{6} = \frac{1}{3} \\ \\ e. \: \: \frac{10}{10} - \frac{5}{10} - \frac{2}{10} + \frac{6}{10} = \frac{10 - 5 - 2 + 6}{10} = \frac{9}{10} \\ \\ f. \: \: \frac{5}{7} + \frac{1}{7} - \frac{4}{7} + \frac{2}{7} = \frac{5 + 1 - 4 + 2}{7} = \frac{4}{7} [/tex]
