a)
1\frac{3}{5} - \frac{7}{9}=\frac{8}{5}-\frac{7}{9}=\frac{72-35}{45}=
b)
2\frac{2}{9} + 1 \frac{5}{12}=\frac{20}{9}+\frac{17}{12}=\frac{80+51}{36}=
c)
3\frac{2}{5} - 5 \frac{2}{3}=\frac{17}{5}-\frac{17}{3}=\frac{51-80}{15}=-\frac{}{15}
d)
4\frac{1}{6}- 2 \frac{7}{15}=\frac{25}{6}-\frac{37}{15}=\frac{125-74}{30}=