[tex]a)\\4 - 2\frac{2}{5} = 3\frac{5}{5}-2\frac{2}{5} = 1\frac{3}{5}\\\\2-1\frac{5}{8} = 1\frac{8}{8}-1\frac{5}{8} = \frac{3}{8}\\\\5 - 3\frac{1}{7} = 4\frac{7}{7}-3\frac{1}{7} = 1\frac{6}{7}[/tex]
[tex]b)\\3\frac{2}{9}-1\frac{5}{6} = 3\frac{4}{18}-1\frac{15}{18} = 2\frac{22}{18}-1\frac{15}{18} = 1\frac{7}{18}\\\\5\frac{2}{7}-2\frac{3}{4} = 5\frac{8}{28}-2\frac{21}{28} = 4\frac{36}{28}-2\frac{21}{28} = 4\frac{15}{28}\\\\2\frac{1}{3}-1\frac{5}{7} = 2\frac{7}{21}-1\frac{15}{21} = 1\frac{28}{21} - 1\frac{15}{28} = \frac{13}{28}[/tex]
