a)
[tex]8\cfrac{4}{11}-5\cfrac{9}{11}=\cfrac{92}{11}-\cfrac{64}{11}=\cfrac{28}{11}=2\cfrac{6}{11}[/tex]
b)
[tex]8\cfrac{5}{6}+5\cfrac{3}{8}=\cfrac{53}{6}+\cfrac{43}{8}=\cfrac{212}{24}+\cfrac{129}{24}=\cfrac{341}{24}=14\cfrac{5}{24}[/tex]
c)
[tex]7\cfrac{2}{3}-4\cfrac{2}{5}=\cfrac{23}{3}-\cfrac{22}{5}=\cfrac{115}{15}-\cfrac{66}{15}=\cfrac{49}{15}=3\cfrac{4}{15}[/tex]
d)
[tex]1\cfrac{2}{7}+4\cfrac{1}{2}=\cfrac{9}{7}+\cfrac{9}{2}=\cfrac{18}{14}+\cfrac{63}{14}=\cfrac{81}{14}=5\cfrac{11}{14}[/tex]
e)
[tex]4\cfrac{8}{15}-3\cfrac{2}{5}=\cfrac{68}{15}-\cfrac{17}{5}=\cfrac{68}{15}-\cfrac{51}{15}=\cfrac{17}{15}=1\cfrac{2}{15}[/tex]