[tex]a. \: \: \: \: \frac{7}{11} + \frac{2}{11} = \frac{9}{11} \\ \\ b. \: \: \: \: \frac{5}{8} + \frac{1}{8} + \frac{2}{8} = \frac{8}{8} = 1 \\ \\ c. \: \: \: \: \frac{ - 15}{4} + \frac{3}{4} = \frac{ - 12}{4} = - 3 \\ \\ d. \: \: \: \: \frac{103}{205} + \frac{ - 71}{205} + \frac{3}{205} = \frac{35}{205} = \frac{7}{41} \\ \\ e. \: \: \: \: \frac{ - 8}{23} + \frac{ - 9}{23} = - \frac{17}{23} \\ \\ f. \: \: \: \: \frac{1}{2} + \frac{1}{3} + \frac{1}{5} nc = 30 \\ \\ = \frac{1 \times 15}{2 \times 15} + \frac{1 \times 10}{3 \times 10} + \frac{1 \times 6}{5 \times 6} = \frac{15}{30} + \frac{10}{30} + \frac{6}{30} = \frac{31}{30} \\ \\ g. \: \: \: \: \frac{2}{7} - \frac{1}{9} nc = 63 \\ \\ = \frac{2 \times 9}{7 \times 9} - \frac{1 \times 7}{9 \times 7} = \frac{18 - 7}{63} = \frac{11}{63} \\ \\ h. \: \: \: \: \frac{ - 10 + 11 - 8}{7} = \frac{ - 7}{7} = - 1[/tex]
