[tex] \frac{2}{9} - \frac{5}{18} [/tex]
[tex] \frac{7}{3} - \frac{12}{30} [/tex]
[tex] \frac{5}{6} + \frac{3}{4} [/tex]
[tex] \frac{2}{7} + \frac{15}{8} [/tex]
​